ESE's works engine tuner

[F5 Dave]

2 piston rings! Well that blows my theories out of the window.


Nah I got nothing, just wanted to appear like I was contributing.

[Flettner]

Hey guys,check this one!!
Give emphasis on the 90mm center to center rod.
I guess that if crankcase don't communicate with tranfers,a long rod isn't needed for bigger case vol!

Why not a short rod, better dwell, as the side load on the piston is not there, it's all taken on an oil feed guide under the piston. This (rod length) is more telling than any thing else, the spacer is almost cetainly to hold this guide (like a large valve guide) as the spacer is NOT needed for a long rod. Easy to seal off the bottom end. 199 exhaust timming I see. If the piston is not touching the bore any more can the exhaust port be wider? How wide before the rings become a problem? It's a pitty we still need rings!

[wobbly]

199 Ex timing is the CIK allowable limit - most all the engine building companies simply put this into the homologation
papers so they dont actually give away the timing they use in reality.

[TZ350]

I have a ti project coming up soon that will go to Zenith. I'll share it with you if it is successful.

Even sharing unsuccessful projects has its merits, we would be interested in those too. As lot can be learned from a project failure and how you went about it, because failure is just another step on the path to success. Win or lose, please post details.

[Flettner]

So I'll share with you what I learned quoting some EBM projects through Zenith.
1) Materials - You can't use aluminum ! Which is really annoying isn't it.....
Aluminium has a vapour phase temp too low for EBM. Basicallly If you tried to do it, you'd inadvertantly create a kind of vapour deposition vaccuum metaliser, coating the entire cabinet in aluminium.
Most materials EBM'd are stainless steel, titanium, or inconel. I believe copper based alloys would be possible, and probably Tungsten. Rocket engines and acid pumps and that kind of thing are what tends to get built in the main.
2) Distortion is controlled with a proprietary method of modelling 'fins' and webs onto the parts to balance them thermally during the build. These are sort of 'stitched' onto the part, and are broken away once the part is completed. This controllled cooling enables much finer forms than can be achieved with SLS. Remember we are talking about titanium and inconel here. SLS of aluminium may not have these distortion issues, but Ti certainly does.
3) Resolution and surface texture is comparable to SLS. Porosity should be much lower but is a compromise with build speed.

I have a ti project coming up soon that will go to Zenith. I'll share it with you if it is successful.

I don't know what to make of it all, we are forever sorting out problems for people getting stuff 3D printed, both plastic and metal.
A recent project involved titanium fingers being printed, we were told the print would be down to 0.05mm, no problem. So the customer turns up with the parts but wants us to machine a 0.5mm slot in them that had only partly printed, where is the 0.05 accuracy? So we have much difficulty holding these parts ( other surfaces also needed machining ) Finally after a lot of time and cost we finish the parts only to have them distort milimeters after some post treating process. Cost the customer a fortune and it all went in the bin! I did tell them at the start that they should just get the parts laser cut out, quicker, cheaper and in the long run more accurate.
It seems to me that the process is a bit like a real small tig welder so there WILL be stress in the final product. Any subsequent heat will cause distortion. Old school has it that you machine the part close to size, stress relieve, then finish. If you are going to print parts for engines I think you will have make the part, stress relieve then finish machining, like we do now.
Not saying don't do it just saying this is one of our experiences, I would get them to put their claims in writing.

[Flettner]

199 Ex timing is the CIK allowable limit - most all the engine building companies simply put this into the homologation
papers so they dont actually give away the timing they use in reality.

SO, is the 11 ports and 90mm rod also " allowable limits " ???

[husaberg]

SO, is the 11 ports and 90mm rod also " allowable limits " ???

One or two of the KZ engines has a 110mm rod. So I think not.
Some have PV's too so they must be allowed those as well.
Remember your bellows gear shift boot seal idea I wonder if a bleed high up could move this and lower the cylinder pressure at the same time Two Birds one stone KISS

[Flettner]

11 transfers and 1 exhaustport!!!

Is it high position transfer ports we see around/above the export?

Very interesting!

Thanks Lef16 for sharing.

11 transfers? are some perhaps unders and some overs, two rows, high pressure and low pressure? Or just lots of little ones?

[wobbly]

A PV isnt allowed in the KZ2 class of 125 CIK engines, and the idea of nominating the number of ports is there
so that although its allowable to remove metal ( NOT adding it ) you cannot increase or change the number of ports
from that stated in the homologation papers.
Rod length is open, but is specified as homologated, but then cannot be changed.

[husaberg]

A PV isnt allowed in the KZ2 class of 125 CIK engines, and the idea of nominating the number of ports is there
so that although its allowable to remove metal ( NOT adding it ) you cannot increase or change the number of ports
from that stated in the homologation papers.
Rod length is open, but is specified as homologated, but then cannot be changed.

What class do the Vortex 125 that have these race in?
314327
I have seen KZ1 mentioned as well whats the difference?
Only reason I noticed it was that it seemed to block of the Sub ports.
314326
Added the balance shaft because it had the factors and dimensions

oh I see its KF2
https://en.wikipedia.org/wiki/KF2

[peewee]

hi frits can you offer some help with a few questions. is there a rule of thumb for how far back in the tunell the exit angle should be and how can we apply the rule of thumb for different size or length of tunells ? for example if we're using the rsa tunells and apply that to a larger engine. i found a radius calculator that will make it faster to transfer the radius to paper then i can trace that to something more rigid like a piece of alloy and use that for the template

the other question and maybe you can only give a estimate but if for example the inner radius is 30mm then would i make the outer wall radius just alittle bigger , so the tunell gets just slightly smaller as it goes to the exit ? this appears to be how the rsw is but then again its only a 2D drawing

[husaberg]

hi frits can you offer some help with a few questions. is there a rule of thumb for how far back in the tunell the exit angle should be and how can we apply the rule of thumb for different size or length of tunells ? for example if we're using the rsa tunells and apply that to a larger engine. i found a radius calculator that will make it faster to transfer the radius to paper then i can trace that to something more rigid like a piece of alloy and use that for the template

the other question and maybe you can only give a estimate but if for example the inner radius is 30mm then would i make the outer wall radius just alittle bigger , so the tunell gets just slightly smaller as it goes to the exit ? this appears to be how the rsw is but then again its only a 2D drawing

I am not Frits, but I do recall a 70% nozzle from memory 4t use a similar principle.

[peewee]

what do you meen 70% nozzle ? im gonna look more at the rsw drawing tomorow and try to figure how much larger the outer wall radius is than the inner wall

[husaberg]

what do you meen 70% nozzle ? im gonna look more at the rsw drawing tomorow and try to figure how much larger the outer wall radius is than the inner wall

Look at the bottom of the transfer port and then the entry to the cylinder.






CSA?? Enlighten me Wob; I do not have that much Kiwi.
Anyway, I can guess that you mean the duct entrance at the cylinder base and yes, it is a bit smaller than the duct exit. But the entrance is open all the time and the exit isn't.This is going to be semantics: of course there is flow from the case into the cylinder, but not in one go. A particle, registered at the crankcase entrance, will show up in the cylinder after four to five crankshaft revolutions, as Wobbly implied.

Jan the maestro himself wondered on a forum somewhere ,about something I realised ages ago,the volume that is held sitting in the transfer ducts is that - that ends up in the cylinder. The case simply refills that volume - there is no " flow " as such from the case into the cylinder even when the pipes big diffuser negative pressure ratio, is creating the max bulk flow around BDC.

How do you find out? Label that particle with radioactivity.
On second thought: don't try this at home.


CSA is a term used in 4T port nomenclature to describe the smallest Cross Sectional Area, usually the venturi under the seat.
But in the Aprilia the CSA at the gasket line is well bigger than the actual CSA down further into the duct, that - is smaller than the chordal flow
area of the port.
Yes, the port is always gradually opening, gradually closing, or blocked, never really thought about that in relation to the duct feeding it.
But I have recognised in the past that really well designed cylinders ( like Calvins Cheetah for the RZ/Banshee ) seem to perform much better than
you would expect from the severely crap duct geometry ( small and very little inner wall ) due to the narrow bore centres.
They have a ton of port area, but the duct volume is very small, simply as there is no room and I believe the the small duct entry/exit ratio plays a large part in
allowing the system to work so well.
Same design route taken by Team Roberts in the Rainey era,they dynoed the factory cylinders to death ( and had a Czech CNC flow visualiser ) and the ducts on those
500s had a huge amount of epoxy added.
Their technology showed up later on the 250s that finally gave Yamaha a title with Jaques on board - that TZ was seriously fast at the time.

[peewee]

ok i know what you meen. hopefully frits will chime in about how far back in the tunell the exit angle of the floor and roof needs to be, referencing my picture above

[Frits Overmars]

ok i know what you meen. hopefully frits will chime in about how far back in the tunell the exit angle of the floor and roof needs to be, referencing my picture aboveNow I think I finally understand what you meant: you weren't asking about an angle at all but about the length of the straight final part of the duct.
It's zero at the floor, which only works if the inner radius is big enough; the length at the roof depends on the axial angle and the port height.

[TZ350]

56mm 125 barrel and have the special crank to show , 108cc

I thought it was a re bore allowance not a de stroke allowance.
But you have got me thinking now ..... :scratch:.... your idea has got me seriously thinking about abandoning the 125cc RGV air cooled project and using the bits to make a water cooled NSR/GP110 with the plenum and fuel injection setup for getting around the 24mm carb restriction.

If destroking a 125 to 110 is allowed under the new rules then I have a good 54mm NSR250 cylinder and with a de stroke of the GP crank by 2mm I could have a 109.9 cc engine with the same bore stroke ratio as the old Suzuki GP125.

A de stroke should be easy as we routinely replace the 19mm Suzuki big end pin with a 22mm Yamaha one. So offsetting it 1mm would not be too hard.

110cc = 54mm bore and 48mm stroke. (has same bore stroke ratio as the 125 Suzuki GP's 56x50)
110cc = 56mm bore and 44mm stroke

So the big question is, would an engine with a 125 cylinder that has been de stroked so its now 110cc be legal??? thoughts please.

[Lightbulb]

Husaberg,
Not sure how to add the quotes you had.
But with the testing we have been doing, it seems that it is about 6 cycles before the mixture change effects the cylinder response. My son has a method of real time measurement of the glow plug wire resistance change, so in effect monitors the combustion chamber for rich or lean. If we have the engine running at peak and pinch the fuel line, there are 6 normal cycles before the plug monitor shows the change in cylinder conditions. Like wise when the engine runs lean and the servo richens the mixture, it is at least 6 cycles before the engine recovers, but to the ears sounds like almost instant.
It makes sense to me the volume being transferred is about that which is in the transfer passages, as often a case is about 4 times the capacity of the engine.
Like others I am really keen to find out how they keep a 125cc engine with a 54mm stroke together at around the 30k limit.
Neil

[husaberg]

Husaberg,
Not sure how to add the quotes you had.
But with the testing we have been doing, it seems that it is about 6 cycles before the mixture change effects the cylinder response. My son has a method of real time measurement of the glow plug wire resistance change, so in effect monitors the combustion chamber for rich or lean. If we have the engine running at peak and pinch the fuel line, there are 6 normal cycles before the plug monitor shows the change in cylinder conditions. Like wise when the engine runs lean and the servo richens the mixture, it is at least 6 cycles before the engine recovers, but to the ears sounds like almost instant.
It makes sense to me the volume being transferred is about that which is in the transfer passages, as often a case is about 4 times the capacity of the engine.
Like others I am really keen to find out how they keep a 125cc engine with a 54mm stroke together at around the 30k limit.
Neil

In the bottom corner of each post is the reply with quote button next to that is the multi quote.
for adding my quotes (that were someone else's) you click the arrow in the quote (after the username ) that takes you to the original post and either use the multi quote or just copy it and then paste it into where you want to use it.
I hope that makes sense.

[Frits Overmars]

So I'll share with you what I learned quoting some EBM projects through Zenith.You can't use aluminum ! Which is really annoying isn't it.No problem at all with aluminium and SLM (SLM=Selective Laser Melting; SLS=Selective Laser Sintering; it's just another designation for the same process.
SLM is the more widely accepted term, as melting is a more accurate description of the process than sintering).


Distortion is controlled with a proprietary method of modelling 'fins' and webs onto the parts to balance them thermally during the build. These are sort of 'stitched' onto the part, and are broken away once the part is completed. This controllled cooling enables much finer forms than can be achieved with SLS.This method was developed for SLM, over 10 years ago, when producing titanium parts for medical use.


EBM Resolution and surface texture is comparable to SLS. Porosity should be much lower.I very much doubt this last claim. The density of SLM-produced parts is exemplary.


I have a ti project coming up soon that will go to Zenith. I'll share it with you if it is successful.Please do, Nick, whether it is successful or not.
http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=314333&stc=1&thumb=1&d=1438510831

[breezy]

Hey guys,check this one!!
Give emphasis on the 90mm center to center rod.
I guess that if crankcase don't communicate with tranfers,a long rod isn't needed for bigger case vol!

i went for the 6 high level, with actuated band control, transfer ports.314336314337

[Frits Overmars]

hi frits can you offer some help with a few questions. is there a rule of thumb for how far back in the tunell the exit angle should be and how can we apply the rule of thumb for different size or length of tunells ? for example if we're using the rsa tunells and apply that to a larger engine. i found a radius calculator that will make it faster to transfer the radius to paper then i can trace that to something more rigid like a piece of alloy and use that for the template.
the other question and maybe you can only give a estimate but if for example the inner radius is 30mm then would i make the outer wall radius just a little bigger , so the tunell gets just slightly smaller as it goes to the exit ? this appears to be how the rsw is but then again its only a 2D drawingGood thinking Peewee. All hell broke loose here because of the Ryger homologation confirmation so I can't find the time to write a decent explanation, but here is a picture of the RSA's A-duct geometry where you can see the inner and outer radii and the coordinates of their centers.
314338

[Frits Overmars]

The international homologation for the 125 cc Ryger kart engine was accepted yesterday. The Federation Internationale de l'Automobile typically needs six weeks to put their paperwork online,
but I will try to make the complete document available sooner than that.

[jonny quest]

Complete document? Does that include basics of what makes the Ryger.... well let's give credit where credit is due... the Ryger?

[jonny quest]

So if the crankcase mixture doesn't see above the piston until after 4 to 5 rev's.... is crankcase just always over filled, and just what's needed is drawn up transfers?

[husaberg]

Complete document? Does that include basics of what makes the Ryger.... well let's give credit where credit is due... the Ryger?

Homologation documents include port maps pipe drawings and pics weight dimensions of crankshafts and pistons.

[jonny quest]

Thanks husaberg, that will be fun! But I have a feeling those documents will still leave us scratching our heads

[breezy]

The international homologation for the 125 cc Ryger kart engine was accepted yesterday. The Federation Internationale de l'Automobile typically needs six weeks to put their paperwork online,
but I will try to make the complete document available later this week.

congratulations..:woohoo::woohoo:

[speedpro]

I'm expecting Flettner will have one running by . . . . Tuesday, this week.

[Martin1981]

"Give emphasis on the 90mm center to center rod.
I guess that if crankcase don't communicate with tranfers,a long rod isn't needed for bigger case vol!"


90mm center to center rod....does that mean that the ryger engine HAS a rod? or does it only mean that the distance between the center of the piston pin and the center of the crank pin is 90mm? if it has a piston pin and a crank pin...

[TZ350]

The international homologation for the 125 cc Ryger kart engine was accepted yesterday. The Federation Internationale de l'Automobile typically needs six weeks to put their paperwork online,
but I will try to make the complete document available later this week.

I am looking forward to this, because I will abandon the RGV air cooled project if its possible for me to build a water cooled 110cc NSR/GP/Ryger engine.

[TZ350]

Interesting thread.


As the title says........Oddball Engines and Prototypes.

[wobbly]

TeeZee,Yamaha was up against it for years by sticking with a 50.6 stroke by 56 bore.
Short strokers ( conventional ) are inherently STA limited and your plan of going 56 by 44 will be seriously compromised
even if you rev it to 20,000 trying to make up for the crap port geometry.

[husaberg]

TeeZee,Yamaha was up against it for years by sticking with a 50.6 stroke by 56 bore.
Short strokers ( conventional ) are inherently STA limited and your plan of going 56 by 44 will be seriously compromised
even if you rev it to 20,000 trying to make up for the crap port geometry.

I don't think its just the STA.
I think the shorter cylinder allows less room for decent shaped transfers on a short stroke esp a twin.

[wobbly]

The only downside I can see to the new engine being CIK homologated is that now it will HAVE to be copied by all the
Italian factories or they will all go out of business .
But if its tied up in any worthwhile patent document, then no one CAN copy it, so karting at the highest level is doomed to a one make
class - good for the patent holder, crap for the sport and everyone else.
Its bad enough now that to stay ahead in the game you are forced to dump perfectly good engines every year and purchase the "better " newly
modified homologated item.
Now ALL engines will be completely outclassed with only 47Hp from a 30mm carbed 125 cylinder,as the Ryger has 70 odd.
Sure, long term and in the wider scope of racing 2Ts the new technology will be a benefit, but as it stands the patent process will completely wreak
karting as we know it.
As you can bet the house on it that a manufacturing licence will cost both arms and legs to purchase.
Same logic applies to the reason we dont have a billion low consumption/emission 2T scooters running around with effective fuel injection, the systems that work are patented.

[jonny quest]

Honest answer Wobbly, if it was your invention. .. wouldn't you be doing same thing?

[ken seeber]

Question for Ken (strike pistons).

Does the Strike PS001 have enough meat around the pin to enable it to be re machined to a 15 or 16mm pin??

With all the MOMs rule changes it now means I can shelve the YZ100 pistons that I current use in favour of a higher quality Kart piston...

Bert, the PS001 pistons we make, from 52 upwards, are designed to suit a Ø14 pin, to open it out to even Ø15 would significantly reduce the strength in that area. One quick option is to use a cage with 2.5 rollers to suit the 15 rod. Could you let us know the basic dimensions of the YZ100 piston, compression height, skirt length and crown shape, as there are many other options out there.

Ryger. Got to agree with Wobbly, could be all sorts of industrial disruptions coming forth. Mind you, the doccos posted are just applications, not necessarily rubber stamped by the CIK. Whether the French care about all the Italian manufacturers is another matter. Can't see why all the secrecy though, as obviously they must have at least a provisional patent in place, you wouldn't do a CIK application unless this was the case. If the design does live up to all the claims, then there are untold applications: single geared kart engines, motocross, jet skis, road bikes, automotive, snowmobiles, 50 hp buckets, new dynos, stronger clutch and gearbox part sales, conversions of existing engines, both 2 and 4 stroke etc.

[husaberg]

well i got the cylinder back from the machine shop and all things considered i think it turned out well. theres now plenty of room for modification of the A ports and the aux exh window can likely be much bigger than i originally thought. the downside is it had to be over bored slightly to get it straight again but thats not a huge deal as i can have a over size piston in a few days. next time ill watch the heat alittle closer but for my first attempt at something like this i think it was a sucess. almost forgot to mention but the exh floor is 5mm higher than bdc now
http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=314306&stc=1&thumb=1&d=1438387136http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=314019&stc=1&thumb=1&d=1438049763


314345314346

[peewee]

wobbly you think ill be fine with 3mm wide bridges between the aux and main exh port or would 3.5 to 4mm be more suitable ? i was thinking to make a oil collection reservoir below the bridges near the bottom of the cylinder wall, similar to the vm cylinder. may even put some small oil holes through the piston in a vertical arrangement that align with the exh bridges. today i gathered about 60 or 70% of the info needed for engine mod. over size piston is ordered then i can finish when it arrives

husaberg i plan to make the exh exit as much like the rsa photo as i possibly can. it wont be exact as that would require fabricating a new manifold from scratch

[wobbly]

NO - Absolutely not.
My choice would be to approach the CIK with a proposal to introduce a completely new class for the engine - and then let it survive and blossom
into all forms of karting ,if it does prove as revelatory as we have been told.

The CIK tried to ditch 2Ts ages ago and introduce some shitter 4T idea,that would drone around like Moto3 does now.
CIKs modus operandi was to reduce emissions etc ,forcing the sport into the expensive 4T death trap set up and promulgated by HRC et al.
But the Italian factories ( and karters in general ) all revolted, and the 2T status quo remained in place.

Now by all reports we have exactly what they wanted, low emissions - with high fuel efficiency, and if the thing is actually mechanically safe
at 30,000,then rev limiting it to 20,000 will make it last indefinitely ( unlike the tyres that last one meeting now with only 47Hp ).

To at one stroke ( not 2 or 4 ) destroy a huge,stable, racing infrastructure by out engineering everyone with a patent protected newcomer in an existing
class ,is in my opinion, patently ( pun intended ) short sighted in the extreme.

But it may all be moot - unless the French really are as arrogant, and pig ignorant, to the dozen Italian manufactures plight in this scenario, as they are/were of
Greenpeace,then the chances of a successful KZ2 homologation hearing are nil.

[husaberg]

wobbly you think ill be fine with 3mm wide bridges between the aux and main exh port or would 3.5 to 4mm be more suitable ? i was thinking to make a oil collection reservoir below the bridges near the bottom of the cylinder wall, similar to the vm cylinder. may even put some small oil holes through the piston in a vertical arrangement that align with the exh bridges. today i gathered about 60 or 70% of the info needed for engine mod. over size piston is ordered then i can finish when it arrives

husaberg i plan to make the exh exit as much like the rsa photo as i possibly can. it wont be exact as that would require fabricating a new manifold from scratch


I included the pics as it looks like you have flattened out the port a bit much, which will make your transition difficult
Making A manifold (IMO) would be easier than modifying your existing one you just need some thick wall pipe and a some flat steel.
You can do the aux cut in's in the manifold with a grinding tool set at about 30 degrees.
314352
The only thing that will actually need a lathe or mill would be the oring groove.
I have a very snazzy one beautifully made out of one piece of steel done on a CNC. Yet it would work no better than one fabricated.


11 transfers? are some perhaps unders and some overs, two rows, high pressure and low pressure? Or just lots of little ones?
I muse that a few are under a higher than bdc ex port

[Lightbulb]

Peewee, that looks really awsome. IT is great when you do a new project and it mostly works the 1st time. I have been lucky like that myself.Great pics. Not to appear to be too dumb, but does it have any form of variable exhaust timing or is it just a fixed exhaust setup.
Neil L

[Frits Overmars]

And now for something completely different: the KTM Jet-ski: http://www.advpulse.com/adv-videos/water-bike-robbie-maddison/

[ken seeber]

And now for something completely different: the KTM Jet-ski http://www.youtube.com/watch?v=lDi9uFcD7XI

Frits, I guessed you noticed that Robbie (an Ozzie as it turns out :clap:) did this on a 2T, same has he did when he did his 2013 Las Vegas building jump. Probably didn’t want to use the Ryger engine though, as he might have overshot the building.

[Frits Overmars]

Frits, I guessed you noticed that Robbie (an Ozzie as it turns out) did this on a 2T, same as he did when he did his 2013 Las Vegas building jump. Probably didn’t want to use the Ryger engine though, as he might have overshot the building.Rumours are that NASA are planning to take their Space Shuttles out of mothballs and replace the rocket engines with Ryger products, so they won't have to buy airmiles space flight time from the Russians any longer.

[teriks]

Husaberg,
Not sure how to add the quotes you had.
But with the testing we have been doing, it seems that it is about 6 cycles before the mixture change effects the cylinder response. My son has a method of real time measurement of the glow plug wire resistance change, so in effect monitors the combustion chamber for rich or lean. If we have the engine running at peak and pinch the fuel line, there are 6 normal cycles before the plug monitor shows the change in cylinder conditions. Like wise when the engine runs lean and the servo richens the mixture, it is at least 6 cycles before the engine recovers, but to the ears sounds like almost instant.

Cool stuff! :)

One thing about the plug resistance measuring. The wire, although a very small mass with a lot of surface area, has a heat capacity and will need some time to react to the new conditions in the combustion chamber.
That may very well be the explanation to some of those six cycles lag you are seeing.

//Thomas

[Frits Overmars]

One thing about the plug resistance measuring. The wire, although a very small mass with a lot of surface area, has a heat capacity and will need some time to react to the new conditions in the combustion chamber. That may very well be the explanation to some of those six cycles lag you are seeing.You do have a point there, Thomas. But we measured the time from main jet to combustion chamber in a spark-ignited engine via a different method and found about five crankshaft revolutions, so Lightbulbs six cycles won't be far off the mark.

[sonic_v]

Why not a short rod, better dwell, as the side load on the piston is not there, it's all taken on an oil feed guide under the piston. This (rod length) is more telling than any thing else, the spacer is almost cetainly to hold this guide (like a large valve guide) as the spacer is NOT needed for a long rod. Easy to seal off the bottom end. 199 exhaust timming I see. If the piston is not touching the bore any more can the exhaust port be wider? How wide before the rings become a problem? It's a pitty we still need rings!

There is still a side load on the piston but the cylinder bore is not carrying the load. The piston has two diameters with the lower part being the smaller diameter. This part of the piston carries the thrust force acting on the bore within the 30 mm plate.

I suspect the short rod is purely for packaging as opposed to any particular engineering reason such as longer dwell at bdc.

It is interesting that the homologation only quotes 1 exhaust port. Will not be surprised if this turns out to actually be 3.

This is unlikely to be remotely as clean - emission wise - as all the claims. The saving in lubrication oil is only a fraction of the unburned hydrocarbons from the fuel. At the one test point that they quoted - 5000 revs/min part throttle - the delivery ratio would be so low that very little fuel goes out of the exhaust port. As soon as the throttle is opened it will be almost as polluting as any other two-stroke without Direct Fuel Injection.

[Frits Overmars]

It is interesting that the homologation only quotes 1 exhaust port. Will not be surprised if this turns out to actually be 3.I would be very surprised if any engine manufacturer would deliberately enter data that would make the homologation invalid.


As soon as the throttle is opened it will be almost as polluting as any other two-stroke without Direct Fuel Injection.You seem to know the engine better than I do :rolleyes:.

[Lef16]

Hey wob,
can you please explain us some basics about 2 stage header?
I think some hundred pages ago you said that a minimun header angle should be 3*.
But what applies for a two-stage header?
And one more,I think that a Honda-style exhaust pipe with the last diffuser been the steepest,could perform better on a street bike with compromise tranfers with small inner radi and without PV.
I'm bulding a pipe for my own bike now,and I think I should prefer this design over Aprilia's "more racing" design.
Cheers

[Haufen]

The only downside I can see to the new engine being CIK homologated is that now it will HAVE to be copied by all the
Italian factories or they will all go out of business .
But if its tied up in any worthwhile patent document, then no one CAN copy it, so karting at the highest level is doomed to a one make
class - good for the patent holder, crap for the sport and everyone else.

I think they will be allowed to copy it if they pay some fees to to the patent holder. But the patent holder has to agree, and the sum is negotiable. But we don't know what exactly has been patented, yet, and if that is responsible for the performance oder eg the emissions only.

I don't know much about the regulating body in karting, but what I read here was that they seem rather strict and eg don't even allow plastic inserts in the crankcase or something like that (Modena?). So, after that I can not come to think of how on earth they would homologate something like the ryger engine. Don't they know what they are doing to their sport in doing so?

[Haufen]

You do have a point there, Thomas. But we measured the time from main jet to combustion chamber in a spark-ignited engine via a different method and found about five crankshaft revolutions, so Lightbulbs six cycles won't be far off the mark.


Did you measure the number of cycles at different rpms, too? What was the influence of the engine speed?

[Frits Overmars]

Did you measure the number of cycles at different rpms, too? What was the influence of the engine speed?We only measured at max.torque rpm. You don't want to spend too much time messing around with radioactive isotopes...

[Frits Overmars]

I don't know much about the regulating body in karting, but what I read here was that they seem rather strict and eg don't even allow plastic inserts in the crankcase or something like that (Modena?). So, after that I can not come to think of how on earth they would homologate something like the ryger engine. Don't they know what they are doing to their sport in doing so?They probably want to make it more environmentally friendly :rolleyes:.

[Haufen]

They probably want to make it more environmentally friendly :rolleyes:.

yeah right :laugh: they should switch to electric powered karts with solar charging then. From the ppm values I saw from the ryger engine, it is not as good as a four stroke, yet, let alone a four stroke with catalytic converter. (If a four stroke can be anything like "good", that is.)


For the radius at the top edge of the exhaust port a practical reason is that it would be quite difficult to get it perfectly tangential with the curvature of the cylinder bore. And for both the exhaust edge radius and the piston edge radius, making them completely tangential will not help the flow.
Both pictures below will show that a full tangential piston edge radius would take away so much of the edge that the ring groove would need to be relocated.
With the piston in BDC it would also create a deeper trough between piston and bore which would create turbulence instead of helping the flow cling to the piston crown. And when the piston is half-way in front of the port and the flow is bumping against it, that lower bit of tangential radius won't make a difference, whether it is there or not.
314215 314214

If you just radius the piston edge, you will increase the port timing and improve the flow. Improving the flow is fine; increasing the timing is not always desirable.
We could drop the cylinder until we have the same angle.areas as before the radiusing, but that does not take the improved flow into account.
What we really ought to do, is include the flow coefficient in the angle.area calculation. But that is beyond the scope of engine simulation programs like EngMod; it would require true 3-dimensional CFD.

By the way, thanks for the above explanation, I got it now. On the VHM website I saw a combustion chamber which was nicely shaped to follow the piston dome with the radiused edge. But that was a design which protrudes into the bore. So I think I can now safely try radiusing, too. Before I saw that picture, I was always afraid that the outside of the dome might distort and provoke detonation.


it would require true 3-dimensional CFD.
And with quite a fine mesh, too! Sometimes I miss all the tools I once had at my disposal. Did they use 3D CFD at Aprilia? Personally, I don't think that's necessary in race engine development, but it sure is a nice help in visualizing the scavenging (and, more importantly, visualizing the differences in scavenging between two variants).

[seattle smitty]

[QUOTE=Haufen] yeah right :laugh: they should switch to electric powered karts with solar charging then . . . (QUOTE]


Alas, not funny. As California goes on regulatory matters, so eventually goes everybody else. And California's chief "expert" on these matters is a 70-year-old woman liberal-arts major and lawyer. www.bloomberg.com/news/articles/2015-08-03/california-regulator-mary-nichols-may-transform-the-auto-industry The actual title of the article features the words, "may end the auto industry as we know it".

[Lightbulb]

Cool stuff! :)

One thing about the plug resistance measuring. The wire, although a very small mass with a lot of surface area, has a heat capacity and will need some time to react to the new conditions in the combustion chamber.
That may very well be the explanation to some of those six cycles lag you are seeing.

//Thomas

In our initial testing this was the case. But my son managed to create a method of recording the resistance in real time to 4 or 5 decimal places . He can record in enough detail, that on every cycle we see what is happening in that cylinder. So he can measure engine rpm over any 6 to 10 cycles and be within 60 rpm of what the digital tacho shows. Although delayed in time , there is still thermal cycling . We can see this up to 32k rpm, we have not yet tested it at higher RPM yet. Other things that have been seen is lean of peak in a cylinder, where rpm remains the same , but the temp drops a very small amount. With glow engines, if the load changes or if you go just a fraction leaner, the temp just rises, and then the engine slows. I think it slows as there is insufficient energy to keep the power to the required level. Then rapidly heats with dramatic slowing. So he is working on a system that keeps it to the rich of peak without being confused with the lean of peak from the programming. There is a hall effect sensor to detect direct crank rpm and is the reference for tdc with an allowance for the lag time of the electronics. It also takes into account pipe pressure average and how that is interrelated to the in cylinder temp and mixture position. I will ask my son for a picture of the glow wire graph in the cylinder if he will let me and post when I can to show you. Neil

[Haufen]

yeah right :laugh: they should switch to electric powered karts with solar charging then . . .


Alas, not funny. As California goes on regulatory matters, so eventually goes everybody else. And California's chief "expert" on these matters is a 70-year-old woman liberal-arts major and lawyer. www.bloomberg.com/news/articles/2015-08-03/california-regulator-mary-nichols-may-transform-the-auto-industry The actual title of the article features the words, "may end the auto industry as we know it".

I think as long as there is no major breakthrough in battery technology, the typical family car 50 years from now will be some kind of hybrid car powered by a small turbocharged combustion engine, consuming half or less of what it would with todays technology. And although I am a fan of highly efficient engines, I must admit that I don't understand the reason why and how CARB wants to regulate some things. (And the by-fact that that woman drives an electric Honda car gives me goosebumps :-D) But I think CARB was never interested in any kind of racing, so let's hope they keep it that way.

By the way, speaking of highly efficient engines, these two companies here are doing quite well with their two-stroke engines, already achieving better specific fuel consumption as todays state of the art diesel engines (whilst also complying with todays emissions legislations). Their application is more truck related, but I would for sure drive a two-stroke powered car, even if it meant that redline rpm would be at 3000 rpm :laugh:

http://www.ecomotors.com/
http://achatespower.com/our-formula/opposed-piston/

[wobbly]

Re the bridges and lubrication.
I routinely add a couple of 1.5mm holes in the piston skirt , slightly offset vertically on each side of the main Ex port, to lubricate
small bridge areas.
Works perfectly.
Re 2 stage headers.
This is where using EngMod will tell you all you need to know.Your average 3.2* incl angle header will be easily beaten in power by a 2 stage
with something like 3.5/5.5* for 2/3 - 1/3 lengths from the piston.
Then if you look at the the diffusers action,and how the angles affect performance - the closer the steeper angle is to the header, the sooner in the cycle around BDC
the biggest depression will be made.
This deep pressure ratio point proportionally moves rightward as the rpm rises, thus its best efficiency range is biased toward peak and overev power.
Where the steepest diffuser is up near the mid section,the deepest pressure ratio occurs late in the cycle around BDC,thus having more scavenging efficiency at lower rpm.
If the ports are also biased to this bandwidth, then the two elements work synergistically and mid power is boosted dramatically at the expense of peak and overev.

[peewee]

husaberg i tried to add more material than i thought i would need so i could grind it down to a desired shape. after looking at the photo i think i understand where i went wrong. like the rsa photo i should start the oval to round transition inside the exh port so the transition will be less extreme. maybe more like this updated photo

lightbulb there is no exh valve on this engine but even if there were im not sure how much good it would do as i only plan to use it for drag racing. the transmission isnt a true close ratio but i think the engine will have enough power that the slightly larger gaps at each gear change wont matter much

[husaberg]

husaberg i tried to add more material than i thought i would need so i could grind it down to a desired shape. after looking at the photo i think i understand where i went wrong. like the rsa photo i should start the oval to round transition inside the exh port so the transition will be less extreme. maybe more like this updated photo



Yes that's more like it. The top of the EX port follows exactly the shape and height of the Port at the cylinder entrance. It just exits downwards following the same 30 degree odd degree slope.
The bottom of the port changes shape curving down near the exit from the flatter profile close to the exit. (I assume to keep the duct volume to the minimum.)
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130807666&highlight=payart#post1130807666
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130810198#post1130810198

314375314376314377314378314385
below click on the arrow after husaberg

Here some pics (attached)if that helps, its no RSA of course. They I believe had a CNC finished Duct.

[peewee]

in engmod it asks for the effective diam of the intake manifold at the point it enters the reed block. ive always assumed this to meen the equivalent diam as my manifold is a rectangle at the point it enters the reed block. in the past ive just used a computer program to convert the rectangle to a equivalent circle diam. ill assume i need to do the same with the exh exit. convert the oval to a equivalent round diam ?

[teriks]

In our initial testing this was the case. But my son managed to create a method of recording the resistance in real time to 4 or 5 decimal places . He can record in enough detail, that on every cycle we see what is happening in that cylinder. So he can measure engine rpm over any 6 to 10 cycles and be within 60 rpm of what the digital tacho shows. Although delayed in time , there is still thermal cycling . We can see this up to 32k rpm, we have not yet tested it at higher RPM yet. Other things that have been seen is lean of peak in a cylinder, where rpm remains the same , but the temp drops a very small amount. With glow engines, if the load changes or if you go just a fraction leaner, the temp just rises, and then the engine slows. I think it slows as there is insufficient energy to keep the power to the required level. Then rapidly heats with dramatic slowing. So he is working on a system that keeps it to the rich of peak without being confused with the lean of peak from the programming. There is a hall effect sensor to detect direct crank rpm and is the reference for tdc with an allowance for the lag time of the electronics. It also takes into account pipe pressure average and how that is interrelated to the in cylinder temp and mixture position. I will ask my son for a picture of the glow wire graph in the cylinder if he will let me and post when I can to show you. Neil
I would love to see that, and anything youd like to share.

The temperature vs AFR I need some time to digest before saying anything.. ;)

[Lef16]

Hey guys,
I don't remember if this has been talked before but as I remember it hasn't.
Im thinking of buying a knock-deto sensor.I've just finished a bike with ~14.1 full stroke CR and it will work with simple 95 pump fuel.
As long as I can't set the advance curve on a dyno I thought that using a knock senor is a good idea.
My question is,will a simple knock sensor from a production car work?I want to connect it with a shift light...what else do I need?
I think that it can be connected to Ignitech but I need a signal tranformer.
And if someone has done it,any help on setting and meause right servo with drum type PV will be appreciated :niceone:
Cheers

[Muciek]

Hey guys,
I don't remember if this has been talked before but as I remember it hasn't.
Im thinking of buying a knock-deto sensor.I've just finished a bike with ~14.1 full stroke CR and it will work with simple 95 pump fuel.
As long as I can't set the advance curve on a dyno I thought that using a knock senor is a good idea.
My question is,will a simple knock sensor from a production car work?I want to connect it with a shift light...what else do I need?
I think that it can be connected to Ignitech but I need a signal tranformer.
And if someone has done it,any help on setting and meause right servo with drum type PV will be appreciated :niceone:
Cheers
Knock sensor,
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page477?p=1130299961#post1130299961

http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130489628&highlight=hysteresis#post1130489628 Talk about setting servos.

[adegnes]

Page 600 has lots of info on the ebay knock gauge.

http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130392745#post1130392745

[husaberg]

Cameron article on Detonation
http://www.klemmvintage.com/camerondeto.htm


The 3 pole ones have 3 wires so dont know how these would be connected.
Most are 2 wire and are common to most late model cars, Audi, VW ,BMW, Subi etc, the plug is standard injector type.
Easiest is the one with 8mm hole thru the middle, they are rugged as hell, so rarely bust, whip down to wrecker and get one for jack shit with the plug connected.


As I said before the knockgauge that works with the Ignitech has an analogue output to ground.
When it detects deto it grounds an Ignitech input that is programmed to retard.
You can watch the lights and then manually take out timing to stop the deto, but the retard circuit of the knockgauge/Ignitech pulls out the timing
so quickly you may well miss this indication.
So I disable the retard initially to see where the advance curve needs to be changed, then reconnect it.
In this case the gauge is a failsafe.

See the pic above of the RSA - the Bosch deto sensor with 8mm hole is bolted to a head stud - that Thiel character was /is no idiot.


Using the det sensor with lights makes it dead easy to shape the curve to suit the engine, you dont need a brake at all.
You can dyno load cycle the engine as fast as you like, and for the short period it may deto, in a small band of rpm - the lights go off like a Xmas tree.
Takes a bit of fiddling with sensitivity to get in the ballpark and read actual deto - not normal noise, as the det frequency is
determined by the bore diameter.
Just make sure the M8 bolt thru the Bosch sensor is tightly fixed to the head or case, with no washers to crush etc.
Data logging the sensor output against rpm is the trick way to go, but simply watching the revcounter and the lights to see where deto is happening during a pull, is easy.
Works just like the deto warning when running EngMod - see the warning and fix the excess advance before a rod comes thru your screen, your choice.

In this case we are dealing with an aircooled scenario - remember two things here, Avgas loves com to make power, and the pipe loves retard to get heat for revon power.
Whenever you have high com or lots of advance a larger % of the heat of combustion is directed out from the chamber into the finning, via mainly the ring contact with
the bore, reduce either or both and more heat ends up in the pipe, making it appear shorter due to the increased wave speed..
Thus when you are thermally limited by the finnings capability to reject heat, you must reduce the heat input by limiting the com.
This then means more heat is available in the pipe, so more power can then be made by upping the advance - just another balancing act.
Its a Catch 22 when there is high dynamic com - ie, when the engine is on the pipe,there is danger lurking, but below that point - the cylinder filling is so piss poor the only way to get good
throttle response off slow corners is to pile in plenty of advance - its safe as houses as there is very little effective com.
This engine has no powervalve so the cylinder filling efficiency comes on slowly, so you roll of the advance slowly, then pull it out quicker as the system starts to work well.
With a powervalve its the opposite - as soon as the valve starts to lift the efficiency increases dramatically, so the advance needs to be pulled out much quicker and sooner.
Any well set up race engine will love 28* below the pipe when running Avgas.

In one of the World Champ skis I did we had 35* of mid advance, as the only time it was in that band was at full throttle from a standing start.
It would jump real hard using that advance to generate cylinder pressure - but troll around on part throttle at that rpm and it would kill the engine by loosening the barrel nuts with rampant deto.


Seems to be some confusion here.
The det sensor has to be connected to the knock gauge I posted the link to on here a while ago.
This has the filter on board as well as led indication.
And if you buy the option of a current sink to ground wire it will drive the retard input on an Ignitech, when deto is seen within the sensitivity range..
Yes any Ignitech input config is shown on the PC screen when it is grounded.



Knock sensor needs to pass through a tuneable band pass filter, seem to remember Jaycar sell a tuneable unit. Will see what I can find.


Yeah, I 'm with Kel; it's about frequency, not voltage amplitude. So, logically, there should be a Fourier transf circuitry and the band-pass filter - all either in physical or pc program form.
I believe it can be done if you know some electronics -and internet browsing-, but the result might not be worthy of the time spent.
The one Wob informed us about has a reasonable price, so why not?


edit :
I don't quite remember at the moment, but there must be some knock signal examples at the Labview website at NI. And some (a little more sophisticated) knock program examples in their forums.

I had the Jaycar page saved in my bookmarks, but it's seems to be no more: www.jaycar.co.nz/productView.asp?ID=KC5444&keywords=knock&form=KEYWORD
It must have been this one : http://www.rhinopower.org/knock/knock.html

Yep, easy to construct a 3D map with tps in the Ignitech by doing runs at 1/4, 1/2 and 3/4 throttle.
Or use the technology properly and use the deto sensor output as well to tell the ecu to retard at any time/rpm when the deto is happening , on the fly.

[ken seeber]

"He is producing the engines himself. And ever since the FIA-homologation was approved, he has been contacted by kart engine importers and dealers all over the world. The amounts they are ordering are astonishing."

If this is the case, there'll certainly be some sadness going around.

[wobbly]

Well if we all end up using the same Ryger engine then thats fine by me - still plenty of scope for "tuning " the things
exactly as we do now,once its on the dyno.
We need Vannick to get the thing modeled asap, so we can begin running sims to see where to go looking for power.

Re the question about the areas used in EngMod.
Yes , whatever shape is at the reed manifold face this needs to be converted to an equivalent circle.
In case you didnt understand, the last section of the intake is the length of the reed block.
But as this varies with petal height off the seat, use 2/3 of the length from the previous face to the tip.
The end diameter is the effective port exit area given to you in the reed analysis.

Then the same logic applies to the Ex duct exit, convert the area to an equivalent circle ( in fact you should be doing this the other way around,EngMod
tells you what the circle should be - you convert this to the oval with ears )
This is done in the Ex port page, but the oval to round transition is then specified as the first section of the pipe input.

[wobbly]

With the PV servo - first thing is to wire up the two circuits independently.
The 3 wires from the position sense pot should be in one plug, the 2 wires for power to the servo motor in another.
Thus when the system is up and running, you can unplug the power to the servo , but see on the screen the mV readings for your full up/full down positions.
Then this is easily programmed in with your own rpm inputs.
The system does a limits check on first powering up, so wind the PV down, then plug in the servo wires with the power to the ecu off.
Once you power up the ecu, it will cycle up and down, if you have the servo polarity wrong, or the pot polarity wrong it wont work.
So again its easy to swap the wires in 1 plug.

[Haufen]

Then the same logic applies to the Ex duct exit, convert the area to an equivalent circle ( in fact you should be doing this the other way around,EngMod
tells you what the circle should be - you convert this to the oval with ears )
This is done in the Ex port page, but the oval to round transition is then specified as the first section of the pipe input.

Wouldn't an oval without ears be better, flow wise? The RSA had ears, of course, but on the other hand, Jan did not complete the exhaust port optimization as he retired at that time. So maybe he would have tested that, at a later point.

[peewee]

i may be wrong here but if there were no ears at the exit , wouldnt the exh tunell need to be much longer so the aux tunells (ears) could merge into the main tunell at the the same gradual angle. thus relocating the manifold much farther down stream where the exh exit finally gets to a round shape. i wonder if the now much longer exh tunell would perform better or worse

[wobbly]

Wrong idea about the ears.
Quit thinking outside the box till you understand whats happening within it.

We have two completely separate regimes operating here, within the Ex duct.
The exit flow of the all important blowdown phase,and the second element, that of the "stored " slug of fuel/ air that is eventually partially returned to the cylinder.
By having the so called "ears" extend all the way down to the header interface we are promoting, as much as possible, the ability of the
blowdowns spent gases to exit the premises with as little hindrance as possible.
This is a proven FACT - take a world champ winning KZ10B engine with a sort of flattened oval exit ,and add the ears right down to the header.
Suddenly it makes shit loads more overev Hp, solely due to the reduction in residual pressure above the opening transfers at high rpm numbers.

Then we have the gradual reduction in the Ex ducts total volume.
This was started thanks to Mr Thiel, by lifting the floor at BDC, and then filling in the bottom corner rads to reduce A port short circuiting as well.
Then the CNC machined floor shape was changed to gradually reduce the total volume,and by inference the step depths.
This goes back to the same idea we now understand about transfer ducts - the flow into the cylinder , mostly at BDC, comes ONLY from the ducts,
not from the case itself.
Thus a small volume sitting in front of the piston is easier to keep cool, has a much increased average velocity into the header,and also is easier for
the return wave to accelerate back the other way ,into the fast closing Ex port.

There is another arrangement that has been hinted at, but I have never actually confirmed, is that Aprilia also extended the so called "ears " down into an oval header
shape, further promoting the all important blowdowns exit geometry.
Sure, Jan retired before he could be convinced by me, or his own intuitive cleverness that steps were a waste of time, but deleting the ears in a 3 port, na, ya dreaming.

[husaberg]

Wrong idea about the ears.
Quit thinking outside the box till you understand whats happening within it.

We have two completely separate regimes operating here, within the Ex duct.
The exit flow of the all important blowdown phase,and the second element, that of the "stored " slug of fuel/ air that is eventually partially returned to the cylinder.
By having the so called "ears" extend all the way down to the header interface we are promoting, as much as possible, the ability of the
blowdowns spent gases to exit the premises with as little hindrance as possible.
This is a proven FACT - take a world champ winning KZ10B engine with a sort of flattened oval exit ,and add the ears right down to the header.
Suddenly it makes shit loads more overev Hp, solely due to the reduction in residual pressure above the opening transfers at high rpm numbers.

Then we have the gradual reduction in the Ex ducts total volume.
This was started thanks to Mr Thiel, by lifting the floor at BDC, and then filling in the bottom corner rads to reduce A port short circuiting as well.
Then the CNC machined floor shape was changed to gradually reduce the total volume,and by inference the step depths.
This goes back to the same idea we now understand about transfer ducts - the flow into the cylinder , mostly at BDC, comes ONLY from the ducts,
not from the case itself.
Thus a small volume sitting in front of the piston is easier to keep cool, has a much increased average velocity into the header,and also is easier for
the return wave to accelerate back the other way ,into the fast closing Ex port.

There is another arrangement that has been hinted at, but I have never actually confirmed, is that Aprilia also extended the so called "ears " down into an oval header
shape, further promoting the all important blowdowns exit geometry.
Sure, Jan retired before he could be convinced by me, or his own intuitive cleverness that steps were a waste of time, but deleting the ears in a 3 port, na, ya dreaming.


If I can be bothered taking a pic side on I will add it here. but the raising of the main port entry actuality also straightens out the duct.
But intuitively by reading what you wrote and having seen a few pics and read some of Frits and Jans musings of late re the raising of the port and the steps.
I do wonder if the steps could be used to actually improve the oval to round transition by extending part of the stub round into a milled recess thus deceasing volume further.
pics to add.
314411

[Flettner]

Wrong idea about the ears.
Quit thinking outside the box till you understand whats happening within it.

We have two completely separate regimes operating here, within the Ex duct.
The exit flow of the all important blowdown phase,and the second element, that of the "stored " slug of fuel/ air that is eventually partially returned to the cylinder.
By having the so called "ears" extend all the way down to the header interface we are promoting, as much as possible, the ability of the
blowdowns spent gases to exit the premises with as little hindrance as possible.
This is a proven FACT - take a world champ winning KZ10B engine with a sort of flattened oval exit ,and add the ears right down to the header.
Suddenly it makes shit loads more overev Hp, solely due to the reduction in residual pressure above the opening transfers at high rpm numbers.

Then we have the gradual reduction in the Ex ducts total volume.
This was started thanks to Mr Thiel, by lifting the floor at BDC, and then filling in the bottom corner rads to reduce A port short circuiting as well.
Then the CNC machined floor shape was changed to gradually reduce the total volume,and by inference the step depths.
This goes back to the same idea we now understand about transfer ducts - the flow into the cylinder , mostly at BDC, comes ONLY from the ducts,
not from the case itself.
Thus a small volume sitting in front of the piston is easier to keep cool, has a much increased average velocity into the header,and also is easier for
the return wave to accelerate back the other way ,into the fast closing Ex port.

There is another arrangement that has been hinted at, but I have never actually confirmed, is that Aprilia also extended the so called "ears " down into an oval header
shape, further promoting the all important blowdowns exit geometry.
Sure, Jan retired before he could be convinced by me, or his own intuitive cleverness that steps were a waste of time, but deleting the ears in a 3 port, na, ya dreaming.

Yar nah, who needs blow down? Ryger 17500rpm (207 BMEP) on single exhaust port :confused:

[philou]

Hello,

extract from an article in the Italian journal mototecnica

What do you think ?

http://img545.imageshack.us/img545/6185/img0218a.jpg

http://img233.imageshack.us/img233/1380/img0027od.jpg

[Frits Overmars]

extract from an article in the Italian journal mototecnica. What do you think ?I think that I'd like to see the wole article. Any chance of a link? Or a scan?

[husaberg]

I think that I'd like to see the wole article. Any chance of a link? Or a scan?

Sounds like some bugger stole my High Rear Transfer Concept.
Or came up with it first without giving me credit.

[philou]

I think that I'd like to see the wole article. Any chance of a link? Or a scan?

I have no other information than those found to link => http://forum.mitoclub.com/topic/92701-travaso-di-pressione

[Frits Overmars]

extract from an article in the Italian journal mototecnica (http://forum.mitoclub.com/topic/92701-travaso-di-pressione). What do you think ?This comes from Mototecnica of March 2011 so I would not call it completely new.
In fact the idea is as old as Methuselah; it's exactly the same idea that Suzuki tried in their 50cc works racer of 1962. It had disappeared in 1963...
314412
PS: Husa, did Suzuki ever give you credit for the idea?

[husaberg]

This comes from Mototecnica of March 2011 so I would not call it completely new.
In fact the idea is as old as Methuselah; it's exactly the same idea that Suzuki tried in their 50cc works racer of 1962. It had disappeared in 1963...
314412
PS: Husa, did Suzuki ever give you credit for the idea?

NO nor any money Don't get me started on Suzuki Frits.:whistle:

<marquee behavior="scroll" direction="right">Don't worry I will be claiming the original idea of the Ryger was mine as soon as I figure out what it is </marquee>

I see they missed the reed Valve though:innocent:
I actually never realised the top of the port was quite that high on the Suzuki(neat pic.)

It was overheating the case... is that right? Or was the Powerband to narrow or both?
Look at that mag placement MZ would not have been ecstatic either.
It looks remarkably like an MZ.
I understand that why they changed the colour of the bikes to Green.

[Frits Overmars]

It was overheating the case... is that right? Or was the Powerband to narrow or both?All of the above.


It looks remarkably like an MZ.Are you playing dumb? Surely you have been around long enough to know the story of MZ works rider Ernst Degner who defected from the German Democratic Workers' Paradise to Japan (trip paid by Suzuki). There are several books about it; one that comes to mind is called "Stealing Speed".


I understand that why they changed the colour of the bikes to Green.Are you implying that MZ choose the coloor of envy? It's the color of Saxonia. The pre-war DKW headquarters were in Szchopau in the heart of Saxonia, since 1922. After the war the company, or what was left of it after the Russians dragged away everything they thought they could use, was renamed to IFA, which carried the colour green, and subsequently, in 1952, to MZ.

[husaberg]

All of the above.

Are you playing dumb? Surely you have been around long enough to know the story of MZ works rider Ernst Degner who defected from the German Democratic Workers' Paradise to Japan (trip paid by Suzuki). There are several books about it; one that comes to mind is called "Stealing Speed".
Are you implying that MZ choose the coloor of Envy? MZs have always been green; it's the color of Saxonia. In fact green was the colour of DKW; their headquarter was in Schopau in the heart of Saxonia. After the war is was briefly renamed to IFA, and subsequently to MZ


Yeah, its not an act though. I posted some stuff Max Oxley I think done. edit its was mac Mcdarmid
I am pretty sure most around here would not have known about the colour change though.
But that engine engine looks so much like the MZ right down to the squared casings
I am not quite that old Frits to remember
I am well young enough to be your son. but Hugh Anderson has stayed at my parents and owes me a clutch lever. I never asked him about the Suzukis though.
I do know the Story of the defections from both accounts including some stuff from Degner, but I think as Walter did, that Honda had a hand in it as well.
From what I understand one of the engines also went to DR JOE.


I think Wobbly said he worked for him? any ideas if that is just a fable Wob?

Pretty sure the original ones were Blue and silver and later green.
Well according to this. When I find it
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130150906#post1130150906
314413
It may not be true but he did interview him. all the old pics I have seen are black and white.


Anderson plus the 50 twin
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130127263#post1130127263
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130128384#post1130128384

[philou]

so there is no interest in sacrificing a cylinder to test

[Frits Overmars]

so there is no interest in sacrificing a cylinder to testOf course there is. Don't just take our word for it; investigate! You'll learn (but don't start with your best cylinder).

[breezy]

Of course there is. Don't just take our word for it; investigate! You'll learn (but don't start with your best cylinder).

thats the way i do it.... the hard way:no::no::no::shit::weep::weep:

[adegnes]

Re the Ryger.

Why just one exhaust port?
- No room for multiples cause other, more inportant(!) holes are in the way?
- That one port is humongous and there are no piston ring, or the ring is the ring, forged in the flames of Mount Doom of Mordor?
- Piston time is slowed down during blowdown while the spent gases are kept @ normal time, no need for much area?
- longer down stroke than up stroke?
- only one exhaust port, but some of the transfers may have serious back flow issues, and just happen to be connected to the pipe?
- theres two sets of transfers and one shared exhaust, the engine has a spark plug below the piston to and fires two times for each cycle - the ping pong engine; now with more better!
- It runs on exhaust gas mixed with melted piston from deliberate runaway deto, one small port to keep the heat at critical levels, and to keep the melting piston from spilling out into the pipe all at once, the stinger nozzle is actually inside the port?
- the whole engine is an optical illusion hiding an efficient electric motor?
- all of the above?

Can't wait to see how simple it really is.
Hope that when it gets revealed it turns out to be just your average racing two stroke with the exhaust bridges removed and zero premix. Guess what, lubrication wasn't needed after all, and the ring didn't break from a 100% single port.

[Haufen]

Thanks for that interesting answer which gave me food for some thoughts (and more questions :) )


Wrong idea about the ears.
Quit thinking outside the box till you understand whats happening within it.

We have two completely separate regimes operating here, within the Ex duct.
The exit flow of the all important blowdown phase,and the second element, that of the "stored " slug of fuel/ air that is eventually partially returned to the cylinder.
By having the so called "ears" extend all the way down to the header interface we are promoting, as much as possible, the ability of the
blowdowns spent gases to exit the premises with as little hindrance as possible.
This is a proven FACT - take a world champ winning KZ10B engine with a sort of flattened oval exit ,and add the ears right down to the header.
Suddenly it makes shit loads more overev Hp, solely due to the reduction in residual pressure above the opening transfers at high rpm numbers.

Then we have the gradual reduction in the Ex ducts total volume.
This was started thanks to Mr Thiel, by lifting the floor at BDC, and then filling in the bottom corner rads to reduce A port short circuiting as well.
Then the CNC machined floor shape was changed to gradually reduce the total volume,and by inference the step depths.
This goes back to the same idea we now understand about transfer ducts - the flow into the cylinder , mostly at BDC, comes ONLY from the ducts,
not from the case itself.
Thus a small volume sitting in front of the piston is easier to keep cool, has a much increased average velocity into the header,and also is easier for
the return wave to accelerate back the other way ,into the fast closing Ex port.

There is another arrangement that has been hinted at, but I have never actually confirmed, is that Aprilia also extended the so called "ears " down into an oval header
shape, further promoting the all important blowdowns exit geometry.
Sure, Jan retired before he could be convinced by me, or his own intuitive cleverness that steps were a waste of time, but deleting the ears in a 3 port, na, ya dreaming.


Is this below the modification you are talking about, above?
If you take a section view of the exhaust port at the point where the the grinding of the ears inside the flange transition just ends, then there is an oval with no ears, too. So maybe this is not so much about the ears, but more something like the ratio between the with of the exhaust port and the width of the grinding for the sub exhaust ports (ears) in relation to the main port width and the distance from the liner, or something like that? Because even the most primitive triple exhaust port will have ears if you take a section view of it that is close enough to the bore.

My sim says there is an increase in Delivery Ratio with a reduction to 75% percent of the effective exhaust diameter at the outlet flange, and a slightly lower Trapping Efficiency. But as the increase in DR is dominant to the loss in TE, there is an increase in power. So do you think that there is a possibility for the suction to become too strong for the transfers to cope with and thus overscavenging the cylinder? This would mean that the 75% ratio would only be valid for high state of tune kind of transfer ports, and that the number would have to be revised to a larger number, eg 85%, for crappier transfer ports.



NO - the aux tunnels should be ground outward at the flange face, then smoothly transition into the round
exit of the spigot.
This pic is of a KZ2 kart cylinder, and the spigot is tapered on the OD, allowing the extended aux width.
The Aprilia is similar but as far as I know they never had a proper smooth transition within the spigot - all the
pics I have seen still had steps.

So the actual duct volume was increased and yet the overrev power increased tremendeously? And the scribed circle at the flange represents the flange exit diameter after the oval to round transition?
Do you happen to have the % numbers of the duct exit in relation to the exhaust area before and after the mod?

[breezy]

Frits, I guess you are right, there is more to this discovery than we might think. If this is what I think it is, then there will also be some VERY interested fourstroke customers, ones that might race in GP class! I can see why you NEED to keep a lid on it.

70bhp@ 125cc.......0.56bhp per 1cc... 900 cc =!!!:eek::eek:

[breezy]

2 piston rings! Well that blows my theories out of the window.


Nah I got nothing, just wanted to appear like I was contributing.

one at the top of the piston ... one at the bottom? bottom one to raise pressure in the transfers to stop back flow down the transfer ports ??

[Frits Overmars]

longer down stroke than up stroke?Yes, the whole engine is slowly disappearing towards the center of the earth.
Now there's an idea: if we mount the engine upside down, it will be great for aero use. Flettner, are you paying attention?
Oh man, Adegnes, I haven't laughed like this in ages :killingme.

[wobbly]

The issue with The TM kart engine ( now completely redundant due to the CIK ) is that we are allowed to remove metal for tuning
NOT add any.
The area at the flange face was 82% before adding the extra ears and was around 86% afterwards.
In reality, if allowed, i would have welded up the floor to reduce the area up into the duct as far as I could, and remade the transition spigot.
But in answer to your question re the Ex depression overscavenging,again,if I could I would be welding up the port bottom corners
and lifting the duct bdc floor to prevent this from happening - no matter what transfer quality was present.
But, as it stands if you are dealing with crap transfers,then creating sufficient blowdown flow or STA ,will also not be an issue,so as you say maybe
the "trick" of extending the ears right down to the round spigot exit is only a necessity when for whatever reason the design becomes Blowdown STA limited
ie full out high bmep designs.

Dr - take the money and run - Joe for sure had that engine,or something like it that no one was supposed to know about.
He had it in a small nailed up case in the workshop,would never even discuss it,and I never understood till years later what that was all about.

[Flettner]

Are there 11 separate reeds in 11 transfer ports? That would certainly stop back flow until the pressure dropped. Then perhaps the transfer ports could be somewhat taller? Lucky I haven't finished the cylinder yet on my test engine :msn-wink:
Although it would be best have the reeds low in the transfers, perhaps part of that spacer plate? This would delay fuel air into the cylinder much like my delayed transfer port injection ie no time to get the fuel air over to the exhaust port and out. Would account for the economy / emissions. Perhaps?
That would have to be a big fat KISS.

[wobbly]

OK, here is the actual info relating to CIK homologation application for the next 3 year period.
Ryger cannot have a CIK approval yet, as the process has only just begun.

The paperwork application to the CIK had to be in by the 1st of August, as approved by the manufacturers local ASN ( ie like Kartsport NZ )
Then the final application numbering from the CIK is issued by the 21st Sept.
For engines there is an inspection period by the CIK between 19th Oct and 30Nov and for homologation purposes there must be 50 completed
units, with components available for 150 total.
The final approval is then published by the CIK for the next 3 year period on 1 Jan 2016.

It will be very interesting to see what transpires, as the CEO of the biggest Italian karting conglomerate is on the CIK board making the approvals.

[Grumph]

OK, here is the actual info relating to CIK homologation application for the next 3 year period.
Ryger cannot have a CIK approval yet, as the process has only just begun.

The paperwork application to the CIK had to be in by the 1st of August, as approved by the manufacturers local ASN ( ie like Kartsport NZ )
Then the final application numbering from the CIK is issued by the 21st Sept.
For engines there is an inspection period by the CIK between 19th Oct and 30Nov and for homologation purposes there must be 50 completed
units, with components available for 150 total.
The final approval is then published by the CIK for the next 3 year period on 1 Jan 2016.

It will be very interesting to see what transpires, as the CEO of the biggest Italian karting conglomerate is on the CIK board making the approvals.

Enjoyable legal fun...if you're not involved....
Wonder if Harry will try and get it homologated as a kit given "over 90%" of an already homologated motor is used ?
If he is basing the unit for homologation on an available motor, and has to produce 50 converted units....Will they sell the units to him for homologation purposes ?
Yep, interesting to watch and see what happens.

[husaberg]

Enjoyable legal fun...if you're not involved....
Wonder if Harry will try and get it homologated as a kit given "over 90%" of an already homologated motor is used ?
If he is basing the unit for homologation on an available motor, and has to produce 50 converted units....Will they sell the units to him for homologation purposes ?
Yep, interesting to watch and see what happens.

Or it could just run in a controlled class of its own.

[wobbly]

No I checked, the Ryger has applied for homologation in an existing class, there are no papers filed to have a new class instigated.
As I opined before, short sighted in the extreme, as they must surely realize that even the most arrogant of French bastards would
have serious misgivings about releasing an engine into an existing class that has near on twice the power, the emissions situation notwithstanding.
So unless of course the high ranking CIK board member Italian CEO, already has a backhanded deal going under the table with Ryger
to have/purchase manufacturing rights ,as I said,I believe the chances of being granted an homologation into an existing class is nil.

[Flettner]

Yes, the whole engine is slowly disappearing towards the center of the earth.
Now there's an idea: if we mount the engine upside down, it will be great for aero use. Flettner, are you paying attention?
Oh man, Adegnes, I haven't laughed like this in ages :killingme.

No, we use the improbability drive, you end up where you least expected to :shit:

[Grumph]

No I checked, the Ryger has applied for homologation in an existing class, there are no papers filed to have a new class instigated.
As I opined before, short sighted in the extreme, as they must surely realize that even the most arrogant of French bastards would
have serious misgivings about releasing an engine into an existing class that has near on twice the power, the emissions situation notwithstanding.
So unless of course the high ranking CIK board member Italian CEO, already has a backhanded deal going under the table with Ryger
to have/purchase manufacturing rights ,as I said,I believe the chances of being granted an homologation into an existing class is nil.

I'm trying not to sound like a conspiracy theorist here.....but.....By any chance does the Board menber's company make the engines Harry R has used as the base for his product ?
I hasten to add i have no knowledge of who makes what - and who's up whom....

[adegnes]

No, we use the improbability drive, you end up where you least expected to :shit:

Hopefully somewhere "mostly harmless".

[F5 Dave]

I don't even like Tea.

[Lightbulb]

I did a search, but could not find any info on Ti pipes and there advantage or their shortfalls. Cost of material is not part of the equation I am looking at. Just from a performance point of view and what makes the very best material for a pipe to make max power with as wide a powerband as possible with good over rev power as well. (A pipe dream, my joke.)
Do they perform better because of the material?
Is there inherent problems due to the low thermal heat conductivity ?
Ti is quite low in expansion, so I imagine they may need to be made a slightly longer tuned length to compensate for both the low length change and a possibly slightly bigger diameter stinger outlet to compensate for a higher average internal temperature.
If making a Ti pipe, what wall section compared to a conventional pipe would be considered ? The same or would it be thinner in order to try and get more heat transferred out of the initial header area ?
Would small longitudinal ribs on the outside of the header in the 1st 5 diameters of length be an advantage to help increase surface area to aid in the cooling of the initial header area?
Any input would be very much appreciated.
Neil

[husaberg]

I did a search, but could not find any info on Ti pipes and there advantage or their shortfalls. Cost of material is not part of the equation I am looking at. Just from a performance point of view and what makes the very best material for a pipe to make max power with as wide a powerband as possible with good over rev power as well. (A pipe dream, my joke.)
Do they perform better because of the material?
Is there inherent problems due to the low thermal heat conductivity ?
Ti is quite low in expansion, so I imagine they may need to be made a slightly longer tuned length to compensate for both the low length change and a possibly slightly bigger diameter stinger outlet to compensate for a higher average internal temperature.
If making a Ti pipe, what wall section compared to a conventional pipe would be considered ? The same or would it be thinner in order to try and get more heat transferred out of the initial header area ?
Would small longitudinal ribs on the outside of the header in the 1st 5 diameters of length be an advantage to help increase surface area to aid in the cooling of the initial header area?
Any input would be very much appreciated.
Neil

Give me a minute, they work no better but are lighter but they need different dimensions due to thermal properties.
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page998?p=1130772641#post1130772641
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page864?p=1130635237#post1130635237
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page1018?p=1130780167#post1130780167
314426

[TZ350]

Since the advent of the 110cc 2T watercooled rule change, I have heard of at least three other 110's being built.

Here is the start of mine. 54mm bore x 48mm stroke for 109.9cc.

314428

Step 1, fit a 11.5mm spacer plate between the GP's cases so that I can run a six speed TS125ER gearbox and clutch instead of the GP's original five speed.

314429

Step 2, a 115mm conrod. The crank used to have a 19mm big end pin. But will now have a 22mm bigend offset 1mm to reduce the stroke to 48mm. And a Mallory metal counter weight plug.

314431

Step 3, 117mm Rotary Valve.

Custom inner RV plate with KE175 rotary valve cover.

314430

Step 4, Custom adapter plate for the rebored (renickosiled a while back) NSR cylinder.

314427

Lots of lovely yummy ports for the watercooled, power valved, never fade all day cylinder.

A totaly in the spirit 110cc H2O, not much to it realy.

And hopefully it won't be to hard to convert this lot to a Ryger engine later, so could this be the start of the first 40+ hp bucket engine....... :niceone:

[Haufen]

Yes, the whole engine is slowly disappearing towards the center of the earth.

Looks like it generates tons of downforce, too :)

[Lightbulb]

Thanks for the info. I will compare the formulas given to the results I have and see what correlations are there with the 2.5cc engine pipe and the 6.5cc engine pipes.
Thanks again, Neil

[Muciek]

Since the advent of the 110cc 2T watercooled rule change, I have heard of at least three other 110's being built.

Here is the start of mine. 54mm bore x 48mm stroke for 109.9cc.

314428

Step 1, fit a 11.5mm spacer plate between the GP's cases so that I can run a six speed TS125ER gearbox and clutch instead of the GP's original five speed.



Ok so You will run a 11,5mm spacer between cases,will You make some sort of stuffer into crankcase between crank webs (horseshoe shape)? Longer custom crank pin to accommodate wider spacing of the bearing in cases? Also wondering on web pins they are not too short?(space for seal and clutch sprocket) Cylinder looks great should be easy to apply some Wobbly and Frits & Jan magic into it :shifty:

[AndreasL]

Wobbly

Sometime ago you said "...a cup of acetone in 5 liters...", do you mean one should add ~0,2l of aceton to 5 liters of ready premix? Or should the acetone be treated "as gas" when doing the calculations?

I know, no big difference, but I like to understand and know things. Even, or should I say especially, the small details. In the end they all add up.

Thanks!

[Peter1962]

I'm trying not to sound like a conspiracy theorist here.....but.....By any chance does the Board menber's company make the engines Harry R has used as the base for his product ?
I hasten to add i have no knowledge of who makes what - and who's up whom....

No, the Ryger is based on an existing 125cc VM. (which is a Chech company)

[adegnes]

Since the advent of the 110cc 2T watercooled rule change, I have heard of at least three other 110's being built.

Here is the start of mine. 54mm bore x 48mm stroke for 109.9cc.

314428

Step 1, fit a 11.5mm spacer plate between the GP's cases so that I can run a six speed TS125ER gearbox and clutch instead of the GP's original five speed.

314429

Step 2, a 115mm conrod. The crank used to have a 19mm big end pin. But now has a 22mm bigend offset 1mm to reduce the stroke to 48mm. And a Mallory metal counter weight plug.

314431

Step 3, 117mm Rotary Valve.

Custom inner RV plate with KE175 rotary valve cover.

314430

Step 4, Custom adapter plate for the rebored (renickosiled a while back) NSR cylinder.

314427

Lots of lovely yummy ports for the watercooled, power valved, never fade all day cylinder.

A totaly in the spirit 110cc H2O, not much to it realy.

And hopefully it won't be to hard to convert this lot to a Ryger engine later, so could this be the start of the first 40+ hp bucket engine....... :niceone:

Love it! :2thumbsup

[F5 Dave]

Not quite sure how you'll work the crank bearings securely and accurately with the spacer plate in, but this alone will be your best mod yet I feel. 6 speed over 5 all day long.

Have you calculated the port timings with such a short stroke? The transfers will never fully open I'd suggest. And the exh floor will be quite low.

[Forgi]

Ryger Engine...

Everybody is just guessing but the most important questions hasn't been asked yet.

1 ex port! Why is it so strange? Maybe that 1 ex port is 100% wide or maybe they've just invented something and the ring on the piston isn't an ordinary one. Or It can be similar to a W port which is also one port. Or maybe the ring doesn't reach the exhaust port.

11 tr ports? If I'd like to put tr ports all around in the cylinder, 4 would be enough. So it has to be a special reason why there are 11. It can be a very special scavenging (ex. vortex), but according to the cylinder's appearance I think it's just the ordinary solution with 5 tr ports.

17k or 30k rpm? The safe piston mean-speed is just a simple rule. I suppose that noone has tried what could happen if a KZ engine or a 125 gp moto is set to 17K.

If I were Wob I have already put a about 600 mm length pipe on a KZ engine and I would examined its power at 17K. I think it would be above 60PS without any modification. What's more I'm sure it would be above 60PS, however it's another thing that at this point the STA values wouldn't be satisfying according to the current and generally accepted principals or mindsets. In my eyes 70HP at 17K doesn't seem so strange at all.

However it is still a mistery to me how is it possible to reach such a rev using a homologe KZ exhaust? I asked this before but it seems nobody cares except me.

I can't understand why didn't they publicated a dyno diagram without the need to saying a word about the engine. If they publicated such data (rpm, power) about the engine I can't understand what made them stop to show the data in papers. We are hearing about 100.000 euro confidental agreement but they haven't got a god damn 30 euro camera or a simple mobile to make a video. A video can't harm any top secret as it doesn't show anything about what is inside the engine. This way they could avoid all the critics and guessing.

Anyway I'm gonna wait for the homologation paper or a video or maybe some sound...but until that moment I take it as if it didn't exist. :rolleyes:

Respect, F.

[TZ350]

Ok so You will run a 11,5mm spacer between cases,will You make some sort of stuffer into crankcase between crank webs (horseshoe shape)? Longer custom crank pin to accommodate wider spacing of the bearing in cases? Also wondering on web pins they are not too short?(space for seal and clutch sprocket)

No stuffers, I want the extra crankcase volume. See Frit's comments below.


.....give the pipe more crankcase volume to breathe from.....


you need a large crankcase volume. Ideally all of this volume should be situated in the transfer ducts. In real life you will also need to lodge part of this volume between crankshaft and piston, i.e: use a long con rod. Avoid nooks and crannies. Crankshafts should be small and smooth. Big end bearings must never be shrouded by recesses in the crank webs or by stuffers.

After Jan Thiel went into retirement in 2008, some geniuses at the factory grabbed their chance to 'correct' the errors that Jan left behind, without even testing the result because 'everybody knows the smaller the crankcase volume the better'. But they never could understand why a 2011 RSA125 was slower than a 2007 model (just look at the 125 cc top speeds on any GP-track). O, the joy of working with Italians.....

And Yes, a longer bigend pin, an RD400 pin might do it, with the longer pin the flywheels will be in their original positions relative to the cases. The six speed gearbox input shaft and drive sprocket all line up because the six speed cluster is 11.5mm wider than the original five speed. In the chassis the left chain side of the engine stays in its original place and the right side moves over 11.5mm, it looks easy enough to do.


Love it! :2thumbsup

Thanks, I am a bit sad to be giving up on the aircooled project. But it just does not make sense to contine with a 125cc air cooled when I can have a 110cc H2O engine even if it has to be restricted by a 24mm :nya:carb, actually I don't think I will be much bothered by the 24mm carb rule because we have learnt a trick or two about getting air flow through a 24mm hole.


Not quite sure how you'll work the crank bearings securely and accurately with the spacer plate in, but this alone will be your best mod yet I feel. 6 speed over 5 all day long.

Have you calculated the port timings with such a short stroke? The transfers will never fully open I'd suggest. And the exh floor will be quite low.

The plan is to dowel everything together for alignment, then use double row self aligning phenolic caged ball races for the mains, we used these before in the Beast. Port timing may have to be corrected with a bit of Devcon and I am planning on fitting an exhaust port floor dam that is very nearly as high as the transfers.

314434

The epoxy sealing around the Ex dam lasted quite well in the aircooled on the dyno and gave good results, so hopefully in a water cooled setup it will be Ok for an extended period of time on the track.

[Frits Overmars]

Ryger production is running in high gear in order to meet the CIK regulations.
314432314433

[Flettner]

Ryger Engine...

Everybody is just guessing but the most important questions hasn't been asked yet.

1 ex port! Why is it so strange? Maybe that 1 ex port is 100% wide or maybe they've just invented something and the ring on the piston isn't an ordinary one. Or It can be similar to a W port which is also one port. Or maybe the ring doesn't reach the exhaust port.

11 tr ports? If I'd like to put tr ports all around in the cylinder, 4 would be enough. So it has to be a special reason why there are 11. It can be a very special scavenging (ex. vortex), but according to the cylinder's appearance I think it's just the ordinary solution with 5 tr ports.

17k or 30k rpm? The safe piston mean-speed is just a simple rule. I suppose that noone has tried what could happen if a KZ engine or a 125 gp moto is set to 17K.

If I were Wob I have already put a about 600 mm length pipe on a KZ engine and I would examined its power at 17K. I think it would be above 60PS without any modification. What's more I'm sure it would be above 60PS, however it's another thing that at this point the STA values wouldn't be satisfying according to the current and generally accepted principals or mindsets. In my eyes 70HP at 17K doesn't seem so strange at all.

However it is still a mistery to me how is it possible to reach such a rev using a homologe KZ exhaust? I asked this before but it seems nobody cares except me.

I can't understand why didn't they publicated a dyno diagram without the need to saying a word about the engine. If they publicated such data (rpm, power) about the engine I can't understand what made them stop to show the data in papers. We are hearing about 100.000 euro confidental agreement but they haven't got a god damn 30 euro camera or a simple mobile to make a video. A video can't harm any top secret as it doesn't show anything about what is inside the engine. This way they could avoid all the critics and guessing.

Anyway I'm gonna wait for the homologation paper or a video or maybe some sound...but until that moment I take it as if it didn't exist. :rolleyes:

Respect, F.

Forget Ryger, forget homologation, the oil less aspect is real I can show that in a running example. The lack of fuel out the exhaust is also a reality with delayed port injection, also displayed in a running example (different engines) but the tech is out there now. 70 hp at 17500, well thats the problem, how? I have my "team" working on that now;).

If the ring was retained so it could just stick out microns, to do the sealing job but not enough to catch in the port, you could have a huge "one" exhaust port. Remember the piston is not wearing against the bore any more. That would give a large exhaust port AREA. No oil carbon to cause the ring to stick.

Interesting times:yes:

[Flettner]

Ryger production is running in high gear in order to meet the CIK regulations.
314432314433

Take the bits of paper out will you.

[wobbly]

We are already up against the reliability limitations of the crankshaft in a KZ2 engine.
The latest versions I have been building will spin to 15200 with good power, if needed, to eliminate several gearchanges per lap
depending upon the track.
If we do this say 3 times per lap for practice,3 heats, a pre final, then a final, then the big end cage will survive just one more meeting with the same abuse.
If its not changed then its all but guaranteed to fail,locking up and probably taking the cylinder with it.
These engines make 47+Hp at the sprocket at 13,000,and in my testing moving the power upward with a shorter pipe will just increase the overev
capability, not make any more peak.
I have machined 3mm off the spigot and 5mm off the face of the duct, as is allowable under the rules, and gained around 300 rpm of overev,no more peak
but lost 3 Hp down at 9000 - way too slow off the hairpin.
We are already blowdown limited, as if the Aux are made any bigger we loose way to much mid power, remember - no PV.
The KZ2 engine would not last a days racing if taken anywhere near 17,000 constantly - the Hp level is irrelevant.


Re the Acetone for oil mixing.
We would put 5L of fuel in the mixing can, add the Acetone, then the oil,but as you say it would make no difference either way.

[Moooools]

If the ring was retained so it could just stick out microns, to do the sealing job but not enough to catch in the port, you could have a huge "one" exhaust port. Remember the piston is not wearing against the bore any more. That would give a large exhaust port AREA. No oil carbon to cause the ring to stick.

Interesting times:yes:

Theory - The ring is retained in the bore instead of on the piston. The piston skirt is long enough such that part of it is always touching the ring, and the piston is nikasil plated. Could explain the need for the big spacer between cylinder and crankcase.

I can't quite work out if this is actually possible without the ring intersecting ports.

Edit: Obviously can be achieved without intersecting ports, but would have to be below all ports. It is not going to do any sort of sealing work down there so that would be stupid. I don't think this theory works.

[Flettner]

Ryger production is running in high gear in order to meet the CIK regulations.
314432314433

Clearly Ryger are confident their engine will get homologation.

[Haufen]

If there's a 90mm rod in there, and there is a spacer plate needed, despite the short rod, then the compression height of the piston could be somewhat bigger than what we're used to in karting (barrel height looks about "normal" to me).

[AndreasL]

Re the Acetone for oil mixing.
We would put 5L of fuel in the mixing can, add the Acetone, then the oil,but as you say it would make no difference either way.

So fuel + aceton in relation to oil when calculate the ratio?

[kel]

Step 4, Custom adapter plate for the rebored (renickosiled a while back) NSR cylinder.

Nicely noted. It wouldn't be legal to use a standard 54mm cylinder unless you reduced the engines capacity to 100cc.

F4 2 stroke 55-100cc
The maximum capacity for rebored engines shall be:
F4 2 stroke 55-110cc

I ended up going with a 50mm cylinder kit, at 99cc there is no questions around the motors compliance with the current rules plus I have the advantage of unrestricted carb size. Of course I now have at least a 3hp handicap
314435
No power valve, but I reckon my exhaust port is bigger than yours ...

[jonny quest]

Plain bearings are much more resilient. Just saying

[peewee]

I am planning on fitting an exhaust port floor dam that is very nearly as high as the transfers.

.

wobbly has said to raise it 2mm immediatly. mine is 5mm. any good reason i shouldnt leave it where its at and try it ?

[husaberg]

Nicely noted. It wouldn't be legal to use a standard 54mm cylinder unless you reduced the engines capacity to 100cc.

F4 2 stroke 55-100cc
The maximum capacity for rebored engines shall be:
F4 2 stroke 55-110cc

I ended up going with a 50mm cylinder kit, at 99cc there is no questions around the motors compliance with the current rules plus I have the advantage of unrestricted carb size. Of course I now have at least a 3hp handicap

No power valve, but I reckon my exhaust port is bigger than yours ...

Just how do you figure a 3 HP handicap, I think you maths is faulty.

[kel]

Just how do you figure a 3 HP handicap, I think you maths is faulty.

You could be right, but don't let the boss know as he might realise I've been winging it all these years :stupid:

[husaberg]

You could be right, but don't let the boss know as he might realise I've been winging it all these years :stupid:
There is no could about it Kel.
The max cylinder size before the 24mm rule applies is 104cc.
Your calculation is based on 100cc 30hp vs 110cc producing a additional 3hp based on an increase in capacity
Yet it is at most more like 1.8 HP as it is 104cc vs 110cc.
But even this potential 1.8hp advantage does not take into account that the over 104cc is restricted in regards to carb size and the below 104cc is currently open carb size.

if you choose to use a smaller cylinder than the rules allow, the handicap is your own doing rather than the rules

[chrisc]

Nicely noted. It wouldn't be legal to use a standard 54mm cylinder unless you reduced the engines capacity to 100cc.

F4 2 stroke 55-100cc
The maximum capacity for rebored engines shall be:
F4 2 stroke 55-110cc

I ended up going with a 50mm cylinder kit, at 99cc there is no questions around the motors compliance with the current rules plus I have the advantage of unrestricted carb size. Of course I now have at least a 3hp handicap
314435
No power valve, but I reckon my exhaust port is bigger than yours ...

Sooooo what happened to the KE engine you were running? I'd love to have a crack at racing that stallion :ar15:

[kel]

Yet it is at most more like 1.8 HP as it is 104cc vs 110cc.


So what is it, did you realise you had jumped the gun with your original reply, or are you (as usual) applying your own interpretation to my statement? Either way, you sure are entertaining.

[kel]

Sooooo what happened to the KE engine you were running? I'd love to have a crack at racing that stallion :ar15:
The 125 air cooler will still get wheeled out for the short races, you're welcome to try it out.
The advantages of running 100cc water cooled are too numerous not to take advantage of, and if I can't crack 30hp I'll just bore it out 110cc.

[husaberg]

So what is it, did you realise you had jumped the gun with your original reply, or are you (as usual) applying your own interpretation to my statement? Either way, you sure are entertaining.

What it is. It is you claiming you are losing out on 3hp If you have not pulled the number from thin air as I have alluded you have.
Feel free to point out how you have not wrongly calculated it. You have had plenty of opportunities to already.
Personally what I find entertaining is just how fervently opposed you were to the proposed rule change allowing an etra few cc to the 100cc water cooled engines to allow 52mm strike pistons to be used (without costly destroking.)
Also how you previously claimed that ethanol fuels would not provide any benefits at all to an air cooled engine when it was that agenda you were pushing at the time.
To the casual observer it would seem to be the agenda that is the correct one for the sport is the one that suits Kel best at the time.

[kel]

Personally what I find entertaining is just how fervently opposed you were to the proposed rule change allowing an etra few cc to the 100cc water cooled engines to allow 52mm strike pistons to be used (without costly destroking.).
Don't remember anything about Strike pistons (once again you are trying to claim things that have never been stated), but you bet I was opposed to a proposed rule change aimed at benefiting MB100 owners that couldn't be bothered doing the work to use 52mm pistons under the previous rules.


Also how you previously claimed that ethanol fuels would not provide any benefits at all to an air cooled engine
specific quote where I state E85 "would not provide any benefits at all to an air cooled engine" No? I didn't think so.

How about you stop clogging up the ESE thread with your pointless attempts at personal attacks, pm me or even give me a call and we can arrange to discuss further when I'm down your way for the BOB :love:.

[lodgernz]

The advantages of running 100cc water cooled are too numerous not to take advantage of, and if I can't crack 30hp I'll just bore it out 110cc.

But then you'll be restricted to a 24mm carb, if I read the new rules correctly?

[Flettner]

I have my "team" working on that now;).

OK team, your turn, Ken.

[husaberg]

Don't remember anything about Strike pistons (once again you are trying to claim things that have never been stated), but you bet I was opposed to a proposed rule change aimed at benefiting MB100 owners that couldn't be bothered doing the work to use 52mm pistons under the previous rules.


specific quote where I state E85 "would not provide any benefits at all to an air cooled engine" No? I didn't think so.

How about you stop clogging up the ESE thread with your pointless attempts at personal attacks, pm me or even give me a call and we can arrange to discuss further when I'm down your way for the BOB :love:.

I am quite happy to never post another single post on this thread if that is what Rob (TZ350) wants.
I never mentioned E85, only ethanol fuels, Nor did the 52mm piston rule change proposal submitted only apply to lazy MB owners. As for personal attacks I think you might want to read what I posted I asked for your methodology. I suggested your addition was faulty.
You choose to construe it as personal. The strike 52mm pistons are the ones that as far as I am aware that are only multiple OS that suit.
I also do agree this thread is not the place. So feel free to carry it on elsewhere at any place of your choosing. I sincerely doubt any degree of proximity to you, will change my position or the opinion that your method of addition is faulty and your position on rules changes contain a huge degree of self serving agendas.

[wobbly]

We Know for a fact that on a 54.5mm stroke race engine lifting the Ex floor several mm made more power.
It was tested properly in a real back to back by Mr Thiel.
Blindly thinking lifting it more will automatically be better is a dangerous assumption, and could well end up like most assumptions
in just being an error waiting to be revealed.
Sure a longer stroke would need alot more, but how much has still actually to be tested properly.
TeeZee tested it on a cylinder that was a good one, he buggered that up in some way, then added a high floor or dam and made it better.
Not very conclusive or scientifically relevant to a non buggered up cylinder.

[husaberg]

Forget Ryger, forget homologation, the oil less aspect is real I can show that in a running example. The lack of fuel out the exhaust is also a reality with delayed port injection, also displayed in a running example (different engines) but the tech is out there now. 70 hp at 17500, well thats the problem, how? I have my "team" working on that now;).

If the ring was retained so it could just stick out microns, to do the sealing job but not enough to catch in the port, you could have a huge "one" exhaust port. Remember the piston is not wearing against the bore any more. That would give a large exhaust port AREA. No oil carbon to cause the ring to stick.

Interesting times:yes:

Kaaden unsuccessfully tried ringless pistons. But his access to metallurgy was known to be poorer than the Japanese or Europeans. yet the Japanese and Euros never went this route either.
Your post there got me thinking about how one some of the tiny aero engines have no rings Secondly if anyone had ever tried a piston design with a Lab type combustion seal arranged of multiple grooved pockets.
Maybe with a better guided piston ring friction and the breaking of seal with tilting is not an issue and design can be different

I do however thing the limiting factor of high speeds breathing limitations was due to blowdown rather than total port area of the EX port. So it might be moot.

[TZ350]

Page 1260 ...


We Know for a fact that on a 54.5mm stroke race engine lifting the Ex floor several mm made more power. It was tested properly in a real back to back by Mr Thiel.


For comparison Honda Rs Scavenge

http://www.solex-competition.net/wp-content/upload/2011/01/Balayage-125-RS-Honda.jpg


If you look at the porting from side on you will se why it is they are arranged like this.
The scavenge pattern is arranged to prevent short circuiting and have the rising columns colliding in such a manner that the they do not escape and are able to fill the cylinder both quickly and efficiently.

Frits from memory did a nice piece on it around xmas 2 years ago
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130452977&highlight=christmas#post1130452977


Pretty sure I have pics of a cut up Honda cylinder.
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130766509&highlight=rs125#post1130766509

Plenty of RS pics here
http://www.kiwibiker.co.nz/forums/album.php?albumid=4841&page=7

The KTM is worth a look pretty much a Honda.
http://www.kiwibiker.co.nz/forums/album.php?albumid=4857

One you posted years ago
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page63?p=1129196083#post1129196083
http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=128246&d=1241260771


There are a few clever enough people ( like Holzer at Modena ) working on kart engine design that I am sure enough R&D has been done to establish if the basic ideas behind Jans Aprilia scavenging works "better" than the current monkey see monkey do Hondarish arrangement.

Problem is that we are dealing with a very different apple to the GP Aprilia. It has a power valve and a mile of clever electronics - a KZ2 has neither.

I have replicated the actual port timing layout ( lower but with B,C opening first ) and this makes considerably better power from peak onwards,but what it gains in overev it looses way more down at 9000.

This is the rpm when exiting the slowest hairpins ( usually only once per lap ) but it is just way too slow at this point that lap times suffer excessively.

I also have replicated the Aux ports ground around to bore centre, and this also makes a HUGE gain in overev power and useable rpm. But in this case it looses some 1.5 Hp at 9000, and this can be got back with plugs in the small end pin.
This loss is easily offset by the fact we can add another tooth on the back and rev it alot harder ( 15,000 ) - lap times drop,so that is a worthwhile gain.

The extra rpm available also allows deleting several between corner gearchanges, again making faster lap times.

The other problem is that it is a big mistake to assume that simply replicating one small element of Jans concept will be a positive step for any old port arrangement.

I know others have tried to add material to the B duct front face, making the wide septum entry, but this then completely changes that front walls entry angle into the cylinder - and this for sure is doomed if the whole reverse stagger,axial angles scenario etc etc isnt used as well..


Those complex 4 stroke behemoths typically flow 70% intake to 30% exhaust, statically on a flow bench.Any ideas what the 2 stroke is statically (obviously pipe is doing quite a bit in the running model)


I can see a long winded answer emerging, Lifting the floor 3mm AND adding 3mm to the bottom corner rads by welding as far in as I could get ( about 20mm ) from the port added around 5% power everywhere in a 125 ie 1 in 20 at the bottom and 2 in 40 at the top,plus slightly more in the overev.

But I stress there is just as much to be had by optimizing the duct exit and spigot geometry.
You are right peewee, make it 3mm high, and add a fillet piece at 6mm high as a test.

The issue with any add in piece is that it wont be cooling the retained slug of A/F in the duct bugger all and this will detract from its overall performance..

There is no correlation to anything with the Ex area below transfer opening, apart from what I mentioned about reducing short circuiting from the A port.

EngMod cannot predict the effects on scavenging and or trapping efficiency when you change the Ex area below TPO, its not a 3D CFD flow visualizer like Fluent etc.

Re the flow regime in the transfer ducts and the Ex duct.
In good designs where everything is pretty much optimized you find that the areas of the ports ( and the intake ) converge.

In fact this is the first element to be looking at in the STA analysis from EngMod - check the 3 areas and go to work on the smallest first.

The Cd will be different but effective flow is way more like 50/50 than what we see in a 4T.


Let's assume a port width of 65% of the bore. Then you can calculate the vertical half-axis.

314786

The minimum safe vertical half-axis becomes
0,7 x (port width / cylinder bore)^4,57 x cylinder bore
= 0,7 x 0,65^4,57 x cylinder bore
= 0,09775 x cylinder bore

Converting this half-axis into center and corner radii can't be done with a simple formula, so I'll do it for you, once-only.
center radius = 88% of bore
corner radii = 5,2% of bore



On the bridged port NiCasil MX engines that I still occasionally do, I send cylinder off with no port chamfering... and instructions for them to not do any chamfering. I only radius top edge of ex port. All other ports I don't even touch. I believe this helps with short circuiting, and a nice consistent transfer opening. Never had a problem with rings

[jonny quest]

Those complex 4 stroke behemoths typically flow 70% intake to 30% exhaust, statically on a flow bench.

Any ideas what the 2 stroke is statically (obviously pipe is doing quite a bit in the running model)

This may give some insight into single Ryger exhaust.

The RSA did what it could with a typical 2 stroke layout.

Very exciting to see this engine development completely outside the box. Basically changing 65 years of development work.

Could you imagine the impact this would have had 10 years ago on the industry?

[peewee]

wobbly im sure the most logical approach would be to start with the floor at bdc and raise until theres no more power but thats alot of work and without a way to measure power you (i) might as well piss in the wind. im still a amatuer with engmod but can it predict any gain from raising the floor ? if i grinded the floor lower i could bring it back up with a dam but anymore welding is out of the picture as the cylinder would just be warped to buggery once again. if nothing else i could just go straight to 2mm and call it good as i would probly see a benefit as well

[karter444]

We Know for a fact that on a 54.5mm stroke race engine lifting the Ex floor several mm made more power.
It was tested properly in a real back to back by Mr Thiel.
Blindly thinking lifting it more will automatically be better is a dangerous assumption, and could well end up like most assumptions
in just being an error waiting to be revealed.
Sure a longer stroke would need alot more, but how much has still actually to be tested properly.
TeeZee tested it on a cylinder that was a good one, he buggered that up in some way, then added a high floor or dam and made it better.
Not very conclusive or scientifically relevant to a non buggered up cylinder.



Big thanks to Wobbly for his advice on shortening the flywheel trigger lobe to fix our engine misfire , it worked . Did our fastest lap of manfield on our no 3 engine . 1.11.8 ,need to find another 1 sec improvement to our race pace , may need some help with that .
I was going to ask a couple of questions regarding exhaust port floor height , you have answered some in the previous post but I will ask some anyway
1. whats the relationship between the pipe , transfer opening duration and the lower half of the exhaust port
2,what is the limiting factor in closing the exhaust port much earlier ie same as transfer opening
3. you said power increased when the port was floor was raised , how much power do you think would be gained and where in the rev range
4. can this be tested on your engmod programme
5. would a alloy plate shaped to fit the port and tack welded into the port duct be ok to test this as welding a port completely may render the barrel useless
cheers

[wobbly]

I can see a long winded answer emerging, but I think less is more in this case as its Friday and we are working up to an AB win..
Lifting the floor 3mm AND adding 3mm to the bottom corner rads by welding as far in as I could get ( about 20mm ) from the port
added around 5% power everywhere in a 125 ie 1 in 20 at the bottom and 2 in 40 at the top,plus slightly more in the overev.
But I stress there is just as much to be had by optimizing the duct exit and spigot geometry.
You are right peewee, make it 3mm high, and add a fillet piece at 6mm high as a test.
The issue with any add in piece is that it wont be cooling the retained slug of A/F in the duct bugger all and this will detract from its overall performance..
There is no correlation to anything with the Ex area below transfer opening, apart from what I mentioned about reducing short circuiting from the A port.
EngMod cannot predict the effects on scavenging and or trapping efficiency when you change the Ex area below TPO, its not a 3D CFD flow visualizer like Fluent etc.

Re the flow regime in the transfer ducts and the Ex duct.
In good designs where everything is pretty much optimized you find that the areas of the ports ( and the intake ) converge.
In fact this is the first element to be looking at in the STA analysis from EngMod - check the 3 areas and go to work on the smallest first.
The Cd will be different but effective flow is way more like 50/50 than what we see in a 4T.

[speedpro]

#2 there would be zero blowdown.

[husaberg]

#2 there would be zero blowdown.

*2 would also result in about 128-136 degrees of Exhaust duration, Which would be number twos. At most revs above idle.

[ken seeber]

Ringless pistons. Of course rings add friction, but the trade-off is that they also provide the proportional sealing of pressures, up to around 90 bar (1300 - 1400 psi) at all sorts of rubbing speeds and high temperatures, not a trivial task. Should they fail, as we’ve all seen with a stuck ring; blowby, loss of lubrication and death.
In a small engine, say a glow plug, one seemingly can get away with it, mainly due to viscous sealing because of the typically 20% oil quantity in methanol &/or nitro fuels, and possibly lower overall temperatures inherent in small engines due to the surface area to volume ratio effect providing a much greater heat transfer rate, at the expense of inherent lower overall thermal efficiencies.
Another thing that has been demonstrated, is that the crevice volume, formed between the bore and the top land above the ring, can result in trapped mixture, leading to unburnt HC emissions. This is why rings have been become higher up the piston. This is not so critical in a stratified charge running condition where, hopefully, only air or burnt gases enter and leave the crevice volume.
I am personally of the belief that a large percentage of the heat from the piston is transferred via the ring and rubbing contact of the ring land (the hottest part of the piston) against the bore. This effect is greatest at the TDC and BDC, where the piston land and ring area have the greatest residency time over the cycle. It is for this reason that cooling of the cylinder is best directed at the very top and also adjacent to the BDC area, usually within the transfer passage cup handles.
If Harry is chucking out all that extra power, relative to current levels, then he will have to provide great attention to the piston cooling, does he have a piston?
As to bearing life, things are going to get tough. 100cc rotary / reeds used to rev to 21k, but there were issues. Sometimes big ends, but with the older vertical reeds aiming between the crankwebs, the big end got much better cooling and lubrication that the now current horizontal reed blocks. Mostly though, it was piston failure, leading to a rod, then unconstrained, scything its way through the crankcases, ignoring all the M6 screws on its way. A 90 mm rod, over the standard VM rod of 110 mm, is going to place more side thrust load on the piston boss area. Maybe if it is a wet sump, using the Honda aerated oil lubrication system and retaining the roller bearings, then this could help, bearing in mind that, with the 25 mm spacer plate, the crank/big end will be more remote from the heat source. If it uses plain bearings, then this pretty much implies some sort of high oil pressure system. Maybe there is no big end at all, but some other clever gizmo. Back to the piston or whatever it is that goes up and down, it will have to be strong to take 30k, but maybe its motion and forces were opposed or dampened, then strength might not be so paramount.
Many a maybe.
He might have done all this and the thing is a real goer with all the claims we have seen. Good on him if this is the case and maybe the world will be a better place. It will inevitably mean change and change means winners and losers. That’s life. But the good thing is that no matter what improvements have been made, things can always be improved. That’s what you bucketeers are all about.

[karter444]

I can see a long winded answer emerging, but I think less is more in this case as its Friday and we are working up to an AB win..
Lifting the floor 3mm AND adding 3mm to the bottom corner rads by welding as far in as I could get ( about 20mm ) from the port
added around 5% power everywhere in a 125 ie 1 in 20 at the bottom and 2 in 40 at the top,plus slightly more in the overev.
But I stress there is just as much to be had by optimizing the duct exit and spigot geometry.
You are right peewee, make it 3mm high, and add a fillet piece at 6mm high as a test.
The issue with any add in piece is that it wont be cooling the retained slug of A/F in the duct bugger all and this will detract from its overall performance..
There is no correlation to anything with the Ex area below transfer opening, apart from what I mentioned about reducing short circuiting from the A port.
EngMod cannot predict the effects on scavenging and or trapping efficiency when you change the Ex area below TPO, its not a 3D CFD flow visualizer like Fluent etc.

Re the flow regime in the transfer ducts and the Ex duct.
In good designs where everything is pretty much optimized you find that the areas of the ports ( and the intake ) converge.
In fact this is the first element to be looking at in the STA analysis from EngMod - check the 3 areas and go to work on the smallest first.
The Cd will be different but effective flow is way more like 50/50 than what we see in a 4T.

would you recommend going correspondingly higher with a 72 mm stroke

[karter444]

#2 there would be zero blowdown.

my mistake question 2 should have read
what is the limiting factor in having the exhaust port fully open by the time the tranfers just open
ie exhaust floor height at the same height as tpo

[Yow Ling]

Has anybody ever tried a labrynth seal instead of rings, just a row of piston ring like grooves around the top of the piston. Sounds too simple to work dunnit

[Ocean1]

Has anybody ever tried a labrynth seal instead of rings, just a row of piston ring like grooves around the top of the piston. Sounds too simple to work dunnit

Fairly high pressure differential for a labyrinth seal. But I'm trying to think how you'd organize a piston to work like a Tesla valve....

[husaberg]

Has anybody ever tried a labrynth seal instead of rings, just a row of piston ring like grooves around the top of the piston. Sounds too simple to work dunnit

I always thought I was invisible............Have a look at the top of the page Mike

[Yow Ling]

I always thought I was invisible............Have a look at the top of the page Mike

I wish I was invisible, what sort of shit do you get up to?

To my credit I spelled it differently

[Flettner]

Kaaden unsuccessfully tried ringless pistons. But his access to metallurgy was known to be poorer than the Japanese or Europeans. yet the Japanese and Euros never went this route either.
Your post there got me thinking about how one some of the tiny aero engines have no rings Secondly if anyone had ever tried a piston design with a Lab type combustion seal arranged of multiple grooved pockets.
Maybe with a better guided piston ring friction and the breaking of seal with tilting is not an issue and design can be different

I do however thing the limiting factor of high speeds breathing limitations was due to blowdown rather than total port area of the EX port. So it might be moot.

Imagine the blow down (time area) on a three port exhaust with no bridges, ie just one large hole, plenty of blowdown area.

[husaberg]

Imagine the blow down (time area) on a three port exhaust with no bridges, ie just one large hole, plenty of blowdown area.

Taking out the bridges I don't think would add significant area well not enough for 30000 rpm anyway. Something more at play in the Ryger.

[Flettner]

Taking out the bridges I don't think would add significant area well not enough for 30000 rpm anyway. Something more at play in the Ryger.

Gas flow past bridges (surface area) will signifcantly slow down.

I remember some years ago reading about the CR 250 1974? having a lot more exhaust area but because of the bridge, in fact flowed less gas than the YZ 250 ( single port).

But you are right there is more going on in the Ryger than this.

[husaberg]

Gas flow past bridges (surface area) will signifcantly slow down.

I remember some years ago reading about the CR 250 1974? having a lot more exhaust area but because of the bridge, in fact flowed less gas than the YZ 250 ( single port).

I am not convinced as the cylinder pressure at blowndown is bloody high. look at how the gases are able to escape those poppet valve curios.
Sure total gas flow will be higher but I don't think that is as much of an issue as the blow down time area.
I am still on the theory they have brought more time with higher delivery pressure of the transfers and or dwelling

[Lightbulb]

I never did try the raised bottom exhaust port, but have seen it done. On the smaller engines it is too hard to tell if it really is and advantage or not.
But one thing I have seen is when the bottom corner of the exhaust was made as a big radius with a 30 deg chamfer slope towards the center. That had a very big negative effect on the engine's performance compared to the 1/16 corner radius and a flat bottomed exhaust. It was done initially as a means of making sure there could not be any sub piston induction. I will have to try the raised floor though and see what the effects are with the smaller engines.
Some one mentioned about labyrinth ring grooves on a piston. These have bee tried by lots of modelers with varying success, but the reality on the model engines is if the surface finish is right to start with and the amount of taper to compensate for the liners growth with the heat. With a properly
made piston and liner surface finish, adding the labyrinth grooves does not make the engine produce any more power or add to the longevity of the sealing ability of the assembly. Better metallurgy was the key for the success of the ringless high performance model engines. With more time and development, I am sure that there could be a combination that could work with bigger piston sizes like those closer to 40mm or 50mm diameter.
A lot of current small engines are using RSP444 which has about 30% silicon in it and is very low expansion material. The trick will be to find a liner material that matches that expansion rate.
Sometimes small changes can have a substantial effect, it is just a matter of finding the combinations that work the best.
Neil

[Frits Overmars]

A lot of current small engines are using RSP444 which has about 30% silicon in it and is very low expansion material. The trick will be to find a liner material that matches that expansion rate.You want a liner that matches the piston's expansion, but not its expansion rate. That would only make sense if the liner became as hot as the piston, which in turn would mean that the piston could no longer transfer its heat to the liner, which would mean the piston would get hotter than the liner: Catch22.

[jonny quest]

On the bridged port NiCasil MX engines I still occasionally do, I send cylinder off with no port chamfering... and instructions for them to not do any chamfering. I only radius top edge of ex port. All other ports I don't even touch. I believe this helps with short circuiting, and a nice consistent transfer opening. Never had a problem with rings

[Lightbulb]

You want a liner that matches the piston's expansion, but not its expansion rate. That would only make sense if the liner became as hot as the piston, which in turn would mean that the piston could no longer transfer its heat to the liner, which would mean the piston would get hotter than the liner: Catch22.

Yeah , you are right Frits, bad wording on my behalf. With some model engines, they make the liners expand slightly more than the piston, so if the engine runs lean and over heats, the engine just looses seal pressure then slows down, or stops. Then if allowed to just cool, it is all fine with no damage to the piston/liner fit. The big end bearing on the rod or the crank pin may have an issue though.
The best engines seem to show no signs of rubbing the piston on the cylinder bore,apart from the seal land area, and I have always assumed that the cooling occurred mainly due to the oil underneath in a 4s situation or the incoming air/fuel in a 2s situation.
Neil

[Flettner]

But then you'll be restricted to a 24mm carb, if I read the new rules correctly?

24mm, doesn't seem to matter, Ryger 70HP on 30mm:shit:

[TZ350]

Honda RS125 Ports as best as I can measure them:-

(F4) (F5) Etc refers to points in the Yamaha SAE paper and can also be seen in Pic-1.

Download the SAE paper from Yamaha on Port Shapes and Power:- http://www.2stroke-tuning.nl/media/pdfjes/porting.pdf


Bore 54mm Stroke 54mm R1=27 (F5) R2=12.5 (F4). The Piston has a very slight dome.

Transfer Port Opens 41.75mm-116 ATDC Inclined Up (F3) 30Deg P1=70 P2=30.

Auxilary Type-1 (F9) Port Opens 43mm-119.5 ATDC Inclined up 15 Deg.

Boost Port Opens 43.5mm-121 ATDC Inclined up 55 Deg.


Pic-1 The Data, Pic-2 The Honda RS125 Ports, Pic-3 The tools for measuring the port angles, Pic-4 The very clean edges in the ports, Pic-5 The piston at BDC, Pic-6 The crankcase port windows.

Now that I am interested in the NSR110cc water cooled engine I looked up the Honda RS port info and Yamaha SAE paper posted earlier on transfer ports. Like Wob and Frits say, the A ports are inclined up the steepest with B much shallower and C (boost port) at 55 deg. The link has pictures and link to a Yamaha SAE paper on transfer ports.

[philou]

For comparison Honda Rs Scavenge

http://www.solex-competition.net/wp-content/upload/2011/01/Balayage-125-RS-Honda.jpg

[husaberg]

Now that I am interested in the NSR110cc water cooled engine I looked up the Honda RS port info and Yamaha SAE paper posted earlier on transfer ports. Like Wob and Frits say, the A ports are inclined up the steepest with B much shallower and C (boost port) at 55 deg. The link has pictures and link to a Yamaha SAE paper on transfer ports.

If you look at the porting from side on you will se why it is they are arranged like this.
The scavenge pattern is arranged to prevent short circuiting and have the rising columns colliding in such a manner that the they do not escape and are able to fill the cylinder both quickly and efficiently.

Frits from memory did a nice piece on it around xmas 2 years ago
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130452977&highlight=christmas#post1130452977


Pretty sure I have pics of a cut up Honda cylinder.
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130766509&highlight=rs125#post1130766509

Plenty of RS pics here
http://www.kiwibiker.co.nz/forums/album.php?albumid=4841&page=7

The KTM is worth a look pretty much a Honda.
http://www.kiwibiker.co.nz/forums/album.php?albumid=4857

One you posted years ago
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page63?p=1129196083#post1129196083
http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=128246&d=1241260771

[goose8]

Does anyone have a bike I could ride tomorrow please for a small fee?

[peewee]

frits i have discovered the secret of ryger. it must use one of these gadgets :woohoo: http://www.ebay.com/itm/Pulse-Injected-Honda-CR-250-Intake-Carburetor-Reeds-/181628290082?hash=item2a49e3c422&vxp=mtr

[breezy]

frits i have discovered the secret of ryger. it must use one of these gadgets :woohoo: http://www.ebay.com/itm/Pulse-Injected-Honda-CR-250-Intake-Carburetor-Reeds-/181628290082?hash=item2a49e3c422&vxp=mtr

can they provide any dyno recorded information?:sherlock:

[nick gill]

A question for Frits (or Luc if you're on here too) now that homologation of the Ryger engine has been achieved, and I assume necessary Patents have been secured even beforehand, what barriers remain before the tech details can be disclosed?
Should we start a Ryger fund, 150 shares at $20 euro each, to buy one in the week they become available?

[Flettner]

A question for Frits (or Luc if you're on here too) now that homologation of the Ryger engine has been achieved, and I assume necessary Patents have been secured even beforehand, what barriers remain before the tech details can be disclosed?
Should we start a Ryger fund, 150 shares at $20 euro each, to buy one in the week they become available?

Nick Gill, may we see what you were machining from that block of alloy?

[husaberg]

Frits,
As a non-loaded question, how many 125 RSW and RSA engines were ever produced and what quantities ever got sold to private teams/individuals?


Jan Thiel Pitlane At Aprilia we always used dental hand pieces.
D&H if I remember well.
We made about 400 cylinders a year, working in a team of 3.
We broke maybe 2 or 3 a year, which was not so bad in my opinion
......................

[Frits Overmars]

There are dental handpieces and dental handpieces. Some you'll find at a dental surgeon's; some you are more likely to find in a Zoo.
314462 314461

[husaberg]

There are dental handpieces and dental handpieces. Some you'll find at a dental surgeon's; some you are more likely to find in a Zoo.


It was more for the number of cylinders.
Is there a easier way to find out how many Aprilia 125 and 250 GP bikes were made.

[Frits Overmars]

Is there a easier way to find out how many Aprilia 125 and 250 GP bikes were made.Nothing I can think of, apart from mailing the Aprilia PR office (no, I haven't got their address nor their phone number).

[husaberg]

Nothing I can think of, apart from mailing the Aprilia PR office (no, I haven't got their address nor their phone number).

I thought of that may be the case, Aprilia must have a pretty impressive register. As I understand that no parts can be ordered without first quoting the engine numbers.

[peewee]

can they provide any dyno recorded information?:sherlock:

probably not but there is some testimonials. that has to account for something :laugh:

[wobbly]

If you look at the legal part of the sonic intakes patent papers, it has lapsed, due to maintenance fees not being paid,need I say more.

But I need some help please Frits.
I am old drinking buddies from Uni with Ron Denis, and he mentioned in a recent email his Honda F1 was proving to be a piece of shit.
So my suggestion was to fit 6 Rygers onto the V6.
Well now that the 1M Euro transfer from McLaren into my Paypal account has gone thru I thought I could start work,and your NDA could easily be made to go away.
The only real problems I have is at each end of the pipe.
But last night I managed to get the 6 into 1 stinger transition working OK in SolidWorks, and now all I really need is the port cores to fit on the other end.
So as its bloody cold here just now it would be great to sit in a pool bar in the Bahamas Hilton and discuss what small changes are needed.
Give Jan a bell and I will arrange the tickets for a couple of weeks work, as im sure he would have a few suggestions on the scavenging regime to help with the project.

[Flettner]

If you look at the legal part of the sonic intakes patent papers, it has lapsed, due to maintenance fees not being paid,need I say more.

But I need some help please Frits.
I am old drinking buddies from Uni with Ron Denis, and he mentioned in a recent email his Honda F1 was proving to be a piece of shit.
So my suggestion was to fit 6 Rygers onto the V6.
Well now that the 1M Euro transfer from McLaren into my Paypal account has gone thru I thought I could start work,and your NDA could easily be made to go away.
The only real problems I have is at each end of the pipe.
But last night I managed to get the 6 into 1 stinger transition working OK in SolidWorks, and now all I really need is the port cores to fit on the other end.
So as its bloody cold here just now it would be great to sit in a pool bar in the Bahamas Hilton and discuss what small changes are needed.
Give Jan a bell and I will arrange the tickets for a couple of weeks work, as im sure he would have a few suggestions on the scavenging regime to help with the project.

Only 1M Euro? you are cheap:lol:
You know, 100,000 Euro is not much of a NDA considering what is at stake.
AND yes yes a V6 !!!

[husaberg]

Only 1M Euro? you are cheap:lol:

He offers free blowjobs for only half the HP of the Ryger.:rolleyes:


PS - if ANYONE can do a 125 Aircooled with 24mm carb and make anything like 30 Hp at 10500, then its here in writing - free blowys for life.

[wobbly]

Na, not a problem.
As we will be staying at her dads best rooms at the Hilton, Im sure I could ring Paris and she would be glad to do the blowys for all of us.

[richban]

So I have one of the very well made ignitech shifter switches. Now I am faced with the choice of ignition cut or Advance reduction in the ignitech settings. I have been told that advance cut is kinder on the gearbox?

Any views from people using this system would be most welcome. Its on the 300 so a touch over 80hp running through what seam like a great street gearbox.

Cheers RB.

[Flettner]

Ryger production is running in high gear in order to meet the CIK regulations.
314432314433

The guided piston (like a large valve guide under the piston) would allow for a short very piston ( apart from the bit to cover exhaust port) so transfers would be real short, just like the little bulges in the side of the cylinder we are seeing. The more I think about this the more I'm convinced there are reeds in each transfer, perhaps that's why we are not allowed to see the dyno results as you would see that the chamber is not upsetting transfer flow off the pipe. When the pipe is working, good, but when it's not at least the transfer flow is not stalled and there by upsetting the intake flow. A tight crank case ( no bottom end involved) would promote high transfer pressures. The transfers closest to the carb would probably be weired off so these reeds are direct from the carb, not through the crank case. ????
The reed block we see incoming from the carb will only have reeds on the bottom (like suzuki mudbug etc) heading down into the crank case, the upper half will have the reeds that feed straight into the cylinder right up near the port walls. Make sense? Remember all transfers can be higher than normal now as the flow will only happen when pressures allow and exhaust pressure can not back track down the transfers into the crankcase at all.
Could it be that simple?

[husaberg]

The guided piston would allow for a short very piston ( apart from the bit to cover exhaust port) so transfers would be real short, just like the little bulges in the side of the cylinder we are seeing. The more I think about this the more I'm convinced there are reeds in each transfer, perhaps that's why we are not allowed to see the dyno results as you would see that the chamber is not upsetting transfer flow off the pipe. When the pipe is working, good, but when it's not at least the transfer flow is not stalled and there by upsetting the intake flow. A tight crank case ( no bottom end involved) would promote high transfer pressures. The transfers closest to the carb would probably be weired off so these reeds are direct from the carb, not through the crank case. ????
The reed block we see incoming from the carb will only have reeds on the bottom (like suzuki mudbug etc) heading down into the crank case, the upper half will have the reeds that feed straight into the cylinder right up near the port walls. Make sense? Remember all transfers can be higher than normal now as the flow will only happen when pressures allow and exhaust pressure can not back track down the transfers into the crankcase at all.

I posted this a while back.
314580
Forget the stuff going on down low.
found this to.
<iframe width="640" height="360" src="https://www.youtube.com/embed/ABNZY3Enykg?feature=player_embedded" frameborder="0" allowfullscreen></iframe>

[wobbly]

Well as we discussed Neil, there is no reed in the intake, the pic shows the carb rubber/manifold only,no reed plate after that.

Rich, the Ignitech ignition cut works perfectly as long as the sensor is really well mounted such that it works identically every shift.
I use a 12V NPN proximity sensor that pulls the input to ground when it sees the head of a pinch bolt on the shaft going into the gearbox.
Set it up so it triggers just as the shift drum starts to actually move, use 40mS cut with 250mS recover time.
You can tell instantly if the shift cut is too long, in that the riders head will jolt forward, as the engine effectively stops.
If its too short, it will be super hard to actually push the lever into the next gear.
I have tried pulling out advance but it seems to work OK in 5th and 6th, but not in 2nd 3rd where you need more time/cut due to the bigger rev drop.
Running speedshift rounds the drive dogs leading edges quickly no matter how its done, and you will get it jumping out of gear if its not undercut.
Boss in Wanganui do a great job, for bugger all.

[richban]

Well as we discussed Neil, there is no reed in the intake, the pic shows the carb rubber/manifold only,no reed plate after that.

Rich, the Ignitech ignition cut works perfectly as long as the sensor is really well mounted such that it works identically every shift.
I use a 12V NPN proximity sensor that pulls the input to ground when it sees the head of a pinch bolt on the shaft going into the gearbox.
Set it up so it triggers just as the shift drum starts to actually move, use 40mS cut with 250mS recover time.
You can tell instantly if the shift cut is too long, in that the riders head will jolt forward, as the engine effectively stops.
If its too short, it will be super hard to actually push the lever into the next gear.
I have tried pulling out advance but it seems to work OK in 5th and 6th, but not in 2nd 3rd where you need more time/cut due to the bigger rev drop.
Running speedshift rounds the drive dogs leading edges quickly no matter how its done, and you will get it jumping out of gear if its not undercut.
Boss in Wanganui do a great job, for bugger all.

Cheers Wob. Racing this weekend so will see how we get on. Also there should be all 4 300's on the grid for the first time. Would be nice to block out the front row with 2 strokes for a change.

[Frits Overmars]

Some help needed please Frits. I am old drinking buddies from Uni with Ron Denis, and he mentioned in a recent email his Honda F1 was proving to be a piece of shit. So my suggestion was to fit 6 Rygers onto the V6.Love the idea. And if you compare the size of a Ryger two-stroke single with a Moto3 foul-stroke engine, you can imagine how beautifully compact that V6 could be.
And imagine the sound of it! Bernie Ecclestone has been complaining about the lack of audio attraction in the present F1 turbo engines. An unsilenced Ryger V6 revving to your heart's desire could easily make that complaint go away.
314586 314587


Well now that the 1M Euro transfer from McLaren into my Paypal account has gone thru I thought I could start work,and your NDA could easily be made to go away.You could make the financial aspect of the non-disclosure agreement go away. But that is not what it's about. I gave my word, simple as that.
Maybe you could spend your money trying to make Ecclestone see the error of his ways when he said "no two-strokes in F1".

don't you love it when you can use the same text twice Wob?

[TZ350]

314591

Chambers and his bike, an RS chassis powered with an RG50 had a good day, Sunday was probably its first real day racing. The bike ran well and Chambers took two second places in F5. It has 21 on it because it is really being setup for Av for when she is back down this way.

Well that was Mt Wellington again, wet in the morning but pretty reasonable in the afternoon for the points races. Two strokes dominated F4 again.

Moools brought his sidecar out for the first time, its pretty good and I think it won both of its points races.

Lots of simple but good features, it has a FXR150 engine and it went really well, the construction looked well engineered but easily done. I would love to see how a 2T with a CVT transmission would go in a sidecar like this.

[husaberg]

Love the idea. And if you compare the size of a Ryger two-stroke single with a Moto3 foul-stroke engine, you can imagine how beautifully compact that V6 could be.
And imagine the sound of it! Bernie Ecclestone has been complaining about the lack of audio attraction in the present F1 turbo engines. An unsilenced Ryger V6 revving to your heart's desire could easily make that complaint go away.
314586 314587

You could make the financial aspect of the non-disclosure agreement go away. But that is not what it's about. I gave my word, simple as that.
Maybe you could spend your money trying to make Ecclestone see the error of his ways when he said "no two-strokes in F1".

don't you love it when you can use the same text twice Wob?

Frits what do you know about the Norton Rotaries Exhaust air cooling drawthrough system. It seemed to be a big pipe mounted on the exhaust that (I think) drew air through the engine using a venturi.
They called it a exhaust-ejector.

I posted a pic ages ago can something like that be used to drawn in additional mixture on a two smoke.

[Frits Overmars]

Frits what do you know about the Norton Rotaries Exhaust air cooling drawthrough system. It seemed to be a big pipe mounted on the exhaust that (I think) drew air through the engine using a venturi. They called it a exhaust-ejector.
I posted a pic ages ago can something like that be used to drawn in additional mixture on a two smoke.In the original Sachs Wankel engine on which the Norton rotary was based (the first Norton racer even had the same port timings as the Sachs) the air/fuel-mixture was drawn from the carburettor into the right-hand side cover, then through the innards of the rotor, through the left-hand side cover and then via a U-turn into the chamber.
314598
This way the rotor was cooled from the inside, but at the same time the mixture was pre-heated considerably, which did the power no good at all.
In the interest of horsepower Norton decided to feed the mixture directly from the carb into the chambers but they wanted to keep the internal air cooling of the rotor, so they used the flow energy of the exhaust gases (which is considerable in a Wankel) to draw air through the rotor. Later they switched to oil cooling for the rotor.

[ken seeber]

[QUOTE=TZ350

. I would love to see how a 2T with a CVT transmission would go in a sidecar like this.[/QUOTE]

The thing is, that I reckon that a piped up 2T scooter is less than exciting, sort of like a Moto3.
The buzz from a 2T is hearing it getting on the pipe prior to each gearchange.
Forget efficiency, go for the sound, trhe sensation and the goosebumps.

[Frits Overmars]

The thing is, that I reckon that a piped up 2T scooter is less than exciting, sort of like a Moto3.
The buzz from a 2T is hearing it getting on the pipe prior to each gearchange. Forget efficiency, go for the sound, trhe sensation and the goosebumps.Yes, that is my only problem with a CVT, Ken. Physically I know that it is better to keep the rpm at a constant level but emotionally I am hooked on hearing the rise of the torque through the rpm rise. That is also one of the charms of an inertial dyno.

[karter444]

can anyone explain why 250 mx cranks need to be so heavy,
could be they need to provide some counter balance for the piston
could. be they need to provide some inertia to maintain a more uniform piston speed under compression and as the piston passes through the transfer stage
or could be to fill crankcase volume
not sure ??

[Ocean1]

can anyone explain why 250 mx cranks need to be so heavy,
could be they need to provide some counter balance for the piston
could. be they need to provide some inertia to maintain a more uniform piston speed under compression and as the piston passes through the transfer stage
or could be to fill crankcase volume
not sure ??

I know that where HP is usually substantially more than required to break traction then weighting up a flywheel makes a bike hook up better...

[wobbly]

250 cranks dont need to be "heavy" as such.
But ss Frits has explained several times the ideal crank has smooth faces with no pockets or cutaways, so this generally means full circle wheels.
It then also has to be able to provide the correct balance factor for the reciprocating assembly.
So alot of each web can be bored all over the place and filled with alloy/plasic, and any extra correction for balance then achieved with Mallory.

It would seem that the FIM are not that keen on a screaming 2T V6 ( but Bernie was quite taken by the blowjob scenario ) so looks like the trip for me
and Frits to the Hilton Bahamas with or without Paris's sexual favors is on hold for now.
It was quite difficult explaining to Ron that my Dutch friend wouldn't spill the beans, so I would have to send back the 1M Euro fee.

[Lef16]

What type of stainless steel do you use for making exhaust pipes?
About a year ago I bought a TIG but I couldn't make it work and I gave it up.
My problem was that it was letting very small holes(ivisible for eyes) in the start and ending of every welding.I figured it out when I leak tested...disaster.... :nono:
I think because of wrong type,or cause of wrong thickness of the rod,or because of the wrong setting...I couldn't understand.
Cheers

[JanBros]

was thinking of the Ryger again :
looking at the pictures :
* looking at the crankcase at the bottom of the 2nd picture, it shows an ordinary boost-port transfer passage (like in a normal 2-stroke).
* looking at the 3rd engine from the bottom, it shows the usual transfer passage for A and B transfers.
* there does not seem to be a passage under the exhaust

314432314433

it just seems impossible to me that there are 11 transfers at the same height in the cylinder (like in a normal 2-stroke). So I thought maybe there are the usual 5 in the cylinder, and 6 somewhere between the crankase and the added spacer, but then again I wouldn't know where the 6th would go.

and if the Ryger has it's own crankcases, why would they still integrate that "look-a-like-bolt-on-a-reed-valve-here" at the front of the cases ? or is that where that bottle goes onto, and why does it have a filter on top ?

http://i18.servimg.com/u/f18/15/75/62/05/ryger-12.jpg

how do you guys think how/where the 11 transfers would be ?

[Flettner]

was thinking of the Ryger again :
looking at the pictures :
* looking at the crankcase at the bottom of the 2nd picture, it shows an ordinary boost-port transfer passage (like in a normal 2-stroke).
* looking at the 3rd engine from the bottom, it shows the usual transfer passage for A and B transfers.
* there does not seem to be a passage under the exhaust

314432314433

it just seems impossible to me that there are 11 transfers at the same height in the cylinder (like in a normal 2-stroke). So I thought maybe there are the usual 5 in the cylinder, and 6 somewhere between the crankase and the added spacer, but then again I wouldn't know where the 6th would go.

and if the Ryger has it's own crankcases, why would they still integrate that "look-a-like-bolt-on-a-reed-valve-here" at the front of the cases ? or is that where that bottle goes onto, and why does it have a filter on top ?

http://i18.servimg.com/u/f18/15/75/62/05/ryger-12.jpg

how do you guys think how/where the 11 transfers would be ?

Ryger are using a standard bottom end so you will see the original transfers in the case. The plate seals all this off as there would be a large valve guide type thing in the middle that the crank is connected to, bottom end is now fourstroke type, plain bearing pressure feed bigend. So all the twostroke stuff goes on above the plate (and in the plate). Easy to imagine 11 transfers, could be one ring of ports on top of another? Because they are using reeds in the transfers and up close to the cylinder ( I think ) there is no need for a conventional reed in the induction as we are used to, this is a red herring. As wobbly points out, there is no reed block sandwiched in there. I don't know, just my observation.

Rod is 20mm shorter and the spacer is approx 25mm taller, add to that a shorter piston, everything seems to "stack" up.

[husaberg]

Ryger are using a standard bottom end so you will see the original transfers in the case. The plate seals all this off as there would be a large valve guide type thing in the middle that the crank is connected to, bottom end is now fourstroke type, plain bearing pressure fed bigend. So all the twostroke stuff goes on above the plate (and in the plate). Easy to imagine 11 transfers, could be one ring of ports on top of another? Because they are using reeds in the transfers and up close to the cylinder ( I think ) there is no need for a conventional reed in the induction as we are used to, this is a red herring. As wobbly points out, there is no reed block sandwiched in there. I don't know, just my observation.

Rod is 20mm shorter and the spacer is approx 25mm taller, add to that a shorter piston, everything seems to "stack" up.

I am with you Neil the cylinder is custom made Ryger. Yet they needed to keep the plate separate from the new cylinder for a reason.

[Grumph]

I am with you Neil the cylinder is custom made Ryger. Yet they needed to keep the plate separate from the new cylinder for a reason.

If - and at this stage it's still a BIG if - there is a guided rod, it still has to be assembled...Given some kind of "normal" small end sizing there's going to have to be some kind of built up bearing/seal assembly on the plate. Also cylinder manufacture is at least easier without a blind end...
Many reasons possible for the separate plate IMO.

[husaberg]

If - and at this stage it's still a BIG if - there is a guided rod, it still has to be assembled...Given some kind of "normal" small end sizing there's going to have to be some kind of built up bearing/seal assembly on the plate. Also cylinder manufacture is at least easier without a blind end...
Many reasons possible for the separate plate IMO.

Likely many, but how do they work when the rod is at least 20mm shorter than standard, yet the cylinder is at least 20mm taller with the added plate.

[Flettner]

Likely many, but how do they work when the rod is at least 20mm shorter than standard, yet the cylinder is at least 20mm taller with the added plate.

Luckily just the right numbers to fit it all in ( plate 25mm by the way )

[RAW]

Luckily just the right numbers to fit it all in ( plate 25mm by the way )

Can't find it at the moment but I'm sure the plate in question is 35mm thick. Anyone have confirmation of this ?

[husaberg]

Luckily just the right numbers to fit it all in ( plate 25mm by the way )


Can't find it at the moment but I'm sure the plate in question is 35mm thick. Anyone have confirmation of this ?

The plot thickens, have to get Ken in to stir it:lol:

[emess]

[QUOTE=Flettner;1130890182] Because they are using reeds in the transfers and up close to the cylinder ( I think ) there is no need for a conventional reed in the induction as we are used to, this is a red herring. As wobbly points out, there is no reed block sandwiched in there. I don't know, just my observation.
/QUOTE]

Mmmm then why go to the trouble of making a reed shaped housing ? :devil2:

(the suspense generated here is better than a load of Hollywood movies)

Mick

[RAW]

314619
Is this the suspect spacer

[ken seeber]

From the pics originally posted by Frits, I had initially estimated the spacer length to be around 25 mm.

Well today, prompted by that Husa, after scaling the VM homologation drawings, remembering that the Ryger cylinder is closely based on this (one can see this when putting the 2 pics side by side, the cylinder length is around 103 mm, from the top deck to the crankcase face. I say around as there is some slight perspective distortion. So, with the latest pics, using this 103 length, the spacer length scales at 20.1 mm. So, to me, I would say a nominal 20 mm, give or take a bee’s dick. In fact, if you look at the spacer and right next to is an M6 cap screw. The head of the cap screw is basically 50% of the thickness of the spacer. Knowing that a M6 screw's head is 10 mm, this supports the 20 mm estimation.

Taking this a bit further. Assuming the piston edge at TDC reaches the same point relative to the barrel and the rod is 20 mm shorter (than a VM) and the compression height of a piston of a generic KZ engine is 29 mm, then the compression height of a possible piston would be 29 + 20 + 20 = 69. Much longer and heavier.

Now, assuming the piston is conventional, in this case Ø54 mm along its full length, and the crankcase is sealed off, then the piston might have an oil scraper ring at the bottom of the skirt. The homologation application doccos indicate 2 rings. One wouldn’t want the oil scraper to uncover the ports at TDC, thereby allowing some communication of oil from the wet sump crankcase into the fresh mixture passages. So, the top of the oil scraper would be around 54 +2 or so, = 56 mm down from the top edge. Given a 2 mm scraper and another 2 mm of material below the ring, then the skirt length would be at least 60 mm. However, if the pin was 69 mm down, this would imply that the piston would need to be much longer to support the pin boss. It would also need to be a full skirt piston. Weight ? 30K?

However, all this could be crap as we don’t really know what is going on, and the above would assume that, as the crankcase delta V was not contributing to drawing any intake charge, there must be some other snazzy method of drawing in the mixture, seemingly way beyond the capacity of a tuned pipe.

Dunno about your spacer pic Rick, it looks too thick to me, but who knows.

Fletto and Husa have suggested all sorts of stepped pistons and they may be right.

Hollywood? haven't seen any women so far in the script, but Wobbly did make mention of Paris. :yawn:

[AndreasL]

314619
Is this the suspect spacer

The clamp in the background looks very small...or the "spacer" is really big if you ask me.

So I say no, not a Ryger.

[speedpro]

Spacer appears to be for a horizontally mounted cylinder - note the oil feed holes up the side of the transfer passage

[TerraRoot]

we must go back, but not as far back as some of the other guys have here, only to the 70's.. it's piston ported!

but seriously, well happy for ryger, really though this would be buried under and lost in patent rubbish for years. Can't wait to see more details!

[190mech]

Best Ryger theory Ive seen yet;

https://www.youtube.com/watch?v=gOAg4XGAzD0&feature=youtu.be

https://www.youtube.com/watch?v=7UfMPi-jUz8&feature=youtu.be

[husaberg]

Best Ryger theory Ive seen yet;

https://www.youtube.com/watch?v=gOAg4XGAzD0&feature=youtu.be

https://www.youtube.com/watch?v=7UfMPi-jUz8&feature=youtu.be
<iframe width="420" height="315" src="https://www.youtube.com/embed/gOAg4XGAzD0" frameborder="0" allowfullscreen></iframe>
Yes and if you add another pumping chamber below the plate communicating with the upper chamber when the piston reaches TDC controlled between the two chambers by a simple flat reed ala Flat plate RG50.
Over 100% cylinder filling can be achieved, as the mixture will also be compressed twice.
This way an aditional intake will take place also while the piston is descending.
It should also cushion the change in velocity both at TDC and BDC.
The mixture intake flow should also be continuous between the two separate chambers rather than start stop. So a small carb will still work efficiently.
The compressed mixture should also take less time to enter the cylinder.
Pretty sure RicM has posted here before or was it Pitlane?

[Flettner]

<iframe width="420" height="315" src="https://www.youtube.com/embed/gOAg4XGAzD0" frameborder="0" allowfullscreen></iframe>


What do you think Ken, close to the money, tight fitting pump for off pipe then tuned length of the pipe straight from the carb through the cylinder via direct ports for high revs.

[wobbly]

And that 90mm rod and bearings survive at 30,000 rpm how?
Even a plain bearing with force fed oiling at 54.5mm stroke has thrown the rod thru the computer screen
at over twice the speeds we see now.

[ken seeber]

Fletto,

I'm in the dark as anyone.

Just thought that we'd add a bit of a reality check. The pics shows a schematic of the overall dimensions and hence constraints. This is based on scaling of the VM homologation drawings and the info from the CIK application.

Rightly or wrongly, we chucked in a piston of full skirt incorporating an oil scraper, pretty much as I described in my earlier post. So, while RicM4 has indicated a neat layout with some clever ideas utilizing a piston rod, I can't see that it could all fit within the overall dimensional envelope, ie the con rod eye passes well beyond the spacer plate.

As a final comment for the day, I wouldn’t be limited to thinking that the current norm of 2A, 2D and 1C passages (as suggested by the externals of the cast cylinder) are really that. There could be anything lurking within.

314624

[husaberg]

And that 90mm rod and bearings survive at 30,000 rpm how?
Even a plain bearing with force fed oiling at 54.5mm stroke has thrown the rod thru the computer screen
at over twice the speeds we see now.

Pretty sure they never said the 30000 rpm was with a single 125 though or did they?
The Foul Stroke 250 MX with a roller big end and similar stroke and rod length achieves pretty close to the revs claimed for the ryger.
But then again I have never actually tachoed one, they sound horrible at MX all sitting they banging on and of the rev limiter on the start line

[Flettner]

Fletto,

I'm in the dark as anyone.

Just thought that we'd add a bit of a reality check. The pics shows a schematic of the overall dimensions and hence constraints. This is based on scaling of the VM homologation drawings and the info from the CIK application.

Rightly or wrongly, we chucked in a piston of full skirt incorporating an oil scraper, pretty much as I described in my earlier post. So, while RicM4 has indicated a neat layout with some clever ideas utilizing a piston rod, I can't see that it could all fit within the overall dimensional envelope, ie the con rod eye passes well beyond the spacer plate.

As a final comment for the day, I wouldn’t be limited to thinking that the current norm of 2A, 2D and 1C passages (as suggested by the externals of the cast cylinder) are really that. There could be anything lurking within.

314624

Don't let reality get in the way of a good story;)

[wobbly]

The CRF250 has a stroke of 53.8 and revs to around 17K so yes the plain bearing pressure oiled crank is reliable at those rpm
exactly as I would expect.
But the Ryger concept has the same stoke near enough, and we believe its a plain bearing "mechanism " of some sort, but
yes ITS reliable at 30,000 rpm we have been told.
Not even remotely the same ballpark.

[husaberg]

The CRF250 has a stroke of 53.8 and revs to around 17K so yes the plain bearing pressure oiled crank is reliable at those rpm
exactly as I would expect.
But the Ryger concept has the same stoke near enough, and we believe its a plain bearing "mechanism " of some sort, but
yes ITS reliable at 30,000 rpm we have been told.
Not even remotely the same ballpark.

I am not sure that is what has been said. I seem to remember some speculation that 30000rpm could be achievable. But there were no claims that I seen that this was with a 54mm stroke and a single though.
I think Harry was pretty forthcoming on the Race hero's of yesteryear thread.

[Flettner]

Fletto,

I'm in the dark as anyone.

Just thought that we'd add a bit of a reality check. The pics shows a schematic of the overall dimensions and hence constraints. This is based on scaling of the VM homologation drawings and the info from the CIK application.

Rightly or wrongly, we chucked in a piston of full skirt incorporating an oil scraper, pretty much as I described in my earlier post. So, while RicM4 has indicated a neat layout with some clever ideas utilizing a piston rod, I can't see that it could all fit within the overall dimensional envelope, ie the con rod eye passes well beyond the spacer plate.

As a final comment for the day, I wouldn’t be limited to thinking that the current norm of 2A, 2D and 1C passages (as suggested by the externals of the cast cylinder) are really that. There could be anything lurking within.

314624

Bet I could fit that all in, just saying I've fit my one in to a smaller space??? My prototype rod / crank / guide assembly that is ;)
You of all people should know Ken, think boomerang:laugh:

[RAW]

And that 90mm rod and bearings survive at 30,000 rpm how?
Even a plain bearing with force fed oiling at 54.5mm stroke has thrown the rod thru the computer screen
at over twice the speeds we see now.

What about the ignition Wobbly, a KZ curve & 30k rpm ?

[Grumph]

The CRF250 has a stroke of 53.8 and revs to around 17K so yes the plain bearing pressure oiled crank is reliable at those rpm
exactly as I would expect.
But the Ryger concept has the same stoke near enough, and we believe its a plain bearing "mechanism " of some sort, but
yes ITS reliable at 30,000 rpm we have been told.
Not even remotely the same ballpark.

There are certain differences though...the 4T with it's "coasting" stroke puts big load reversals into the rod and pins. The 2T is always under compression which should make a difference.
Not saying you're wrong, I don't have the computing power available to quantify it...

RAW - If I remember correctly, Honda found when going over 20,000 rpm with their multis that the ignition point became less important, almost irrelevant as long as it ran some advance. You'd wonder if, at those revs,the fire ever went out...glowplugs anyone ?

[husaberg]

There are certain differences though...the 4T with it's "coasting" stroke puts big load reversals into the rod and pins. The 2T is always under compression which should make a difference.
Not saying you're wrong, I don't have the computing power available to quantify it...

RAW - If I remember correctly, Honda found when going over 20,000 rpm with their multis that the ignition point became less important, almost irrelevant as long as it ran some advance. You'd wonder if, at those revs,the fire ever went out...glowplugs anyone ?

Octane became irrelevant at high revs. Not sure if the advance was though. Those early 4V Hondas needed plenty of advance initially anyway up to 50 degrees I think , due to the wide valve angles dictated by the air cooling they had causing the inefficient combustion chamber shape.

[Frits Overmars]

... if you add another pumping chamber below the plate communicating with the upper chamber when the piston reaches TDC controlled between the two chambers by a simple flat reed ala Flat plate RG50. Over 100% cylinder filling can be achieved, as the mixture will also be compressed twice.So wouldn't it be better to add still another pumping chamber? Or ten of those?
If you let your lower chamber communicate with the upper chamber, the compressing chamber simply moves the mixture to the expanding chamber. One chamber breathing to or from another won't give you double-pumping action; it will only violate KISS. You can compress the mixture as many times as you want; it won't change the amount of mass that was initially inhaled.
Double-pumping requires each chamber to breathe from atmosphere and into a receiver, but this would be a clear violation of the 'no supercharging' rule found in most rulebooks.


Pretty sure RicM has posted here before or was it Pitlane?RicM = Rick Maas; he is the Dutch guy who built the servo-controlled trombone pipe that I presented here some time ago.

[wobbly]

Frits has categorically said several times that the 125 kart engine makes 70 Hp @ 17K and revs to 30,000.
And he is a man I respect - who wont say what he isnt allowed to, but for sure I believe what he does actually say.
The homolgation application papers show the bore/stroke and rod length for that single cylinder 125 engine he
has been talking about.

That engine if it gets passed by the CIK it must run the homologated PVL analogue ignition with all but a straight line advance curve.
I have test bench graphs from PVL that show plenty of ignition power up to 20,000 so maybe its OK at another 10,000.
It must be as Frits has driven the thing at 30,000 in reality - havnt you been watching.

[husaberg]

So wouldn't it be better to add still another pumping chamber? Or ten of those?
You can compress the mixture as many times as you want; it won't change the amount of mass that was initially inhaled. If you let your lower chamber communicate with the upper chamber, the compressing chamber simply moves the mixture to the expanding chamber. One chamber breathing from another won't give you double-pumping action; it will only violate KISS.
Double-pumping requires each chamber to breathe from atmosphere and into a receiver, but this would be a clear violation of the 'no supercharging' rule found in most rulebooks.

RicM = Rick Maas; he is the Dutch guy who built the servo-controlled trombone pipe that I presented here some time ago.

The idea of the double pumping was more to allow continuous induction it would alternately breath through the upper and lower in turns . The crankcase does a similar thing on a two stroke.
In practice the under and over pumping would be pumping no more that the actual capacity of the cylinder wouldn't it? so technically legalish.
Regardless If the mixture was compressed, wouldn't it be able to flow faster buying valuable time.
Bugger the rules they are made by four stroke people anyway.:laugh:

Thought the name rung a bell.............

[Frits Overmars]

Frits has categorically said several times that the 125 kart engine makes 70 Hp @ 17K and revs to 30,000.
And he is a man I respect - who wont say what he isnt allowed to, but for sure I believe what he does actually say. The homolgation application papers show the bore/stroke and rod length for that single cylinder 125 engine he has been talking about.
That engine if it gets passed by the CIK it must run the homologated PVL analogue ignition with all but a straight line advance curve.
I have test bench graphs from PVL that show plenty of ignition power up to 20,000 so maybe its OK at another 10,000.
It must be as Frits has driven the thing at 30,000 in reality - havnt you been watching.Thanks Wob. What's your poison?
You're quite right about the ignition. In fact the Ryger prototype has been running all year with the CIK-homologated fixed-advance PVL ignition.

[husaberg]

Took the Ryger-kart for a little spin today.
God Almighty!
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I've got a fairly good idea of what to expect from a 125 cc kart. But this....
The revcounter could hardly keep up with the crankshaft but in any case it revved much higher than a normal 125 and I reached the end of the straight-away much quicker. What a rocketship!


Don't bother deciphering that patent; it's not the Ryger-patent. The Ryger engine is much simpler.


Thank god, finally a remark that I can comment on without violating the Ryger non-disclosure agreement.
Yes, you could employ an additional reed. But why would you? The 24/7 valve itself is a reed; how much simpler do you want things to be?


Husa, here is a rule of thumb: a racing two-stroke consumes about 7 cc fuel per hp per minute (the Ryger engine consumes considerably less).

Ken, you might want to review your correlation as the RSA produces its 54 hp @ 13,000 not 12,000 rpm.


I'm happy to say that patent http://worldwide.espacenet.com/publicationDetails/mosaics? (http://worldwide.espacenet.com/publicationDetails/mosaics?CC=WO&NR=2013185802A1&KC=A1&FT=D&ND=3&date=20131219&DB=EPODOC&locale=en_EP) is not the Ryger patent. And I agree: it's far too complicated.
Must hurry now, couldn't even find the time to read your whole post, Ken. I'll get back to you if there is anyting that I am allowed to comment on.


It would certainly put the RG-trannie to the test. 280 hp, that's 50 horses more than what the current 1000 cc MotoGP bikes have, with all their electronic gizmos, meant to keep their riders on the track and out of hospital.

Like a regular 125 cc kart engine, until you rev it through the ceiling. Lovely sound!:wings:


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Yep, this is the cylinder, and here is what Harry Ryger wrote:


Your idea looks rather simple compared to some suggestions I've seen here. But your pumping cylinder is moved by crankcase pressure alone, right?
It may function at 3.000 rpm, but the Ryger revs past 30.000 if you keep your foot down (which I did the first time I gave it some throttle, because I expected 125 cc kart-like acceleration, not the rocket launch I got) .


Yep.
Here are two links showing the standard VM 125-engine.

VM 125 M 02/B catalogue: http://www.vmmotor.com/www/vmmotor/fs/catalogue-vm125-m02-beng.pdf

VM homologation: http://mach1motorsport.files.wordpress.com/2012/03/homologering-vm.pdf

I didn't count them but I estimate that in the Ryger engine 98% of these parts are used unmodified, including the cylinder head.


Asked and answered, Your Honour: http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130868700#post1130868700

I can envisage a free piston engine surrounded by coils, acting as a generator and driving an electromotor. But that's for next month.


I'm not at liberty to answer that.


Not necessarily. For example, a piece breaking off the piston skirt will not do the rpm much good, generally.
Joking apart, a while back I would have answered that the attainable rpm in a two-stroke is limited by the time.areas, not by piston speed or mass.
But that was BR (Before Ryger).

Whole pistons have been made from pressed carbon (the kind that carbon brushes are made of). Mahle experimented quite a bit with them, mainly for TDI engines, but they made some two-stroke pistons as well. They are self-lubricating and will withstand very high temperatures, but they are not much lighter than light-alloy pistons because they require thicker skirt walls, and their high crown temperature will provoke detonation, which makes them unsuitable for anything but diesels.
312538


You made my day, Jan; you fell for it 38 years after the fact. That magazine was MOTO 73, of which I was the technical editor (and test rider, and photographer, and translator, and I also made the coffee occasionally, but somehow we managed to become the biggest motorcycle magazine in the Netherlands and Belgium).
The TVPS (Top Valve Piston System) was our 1977 April Fool's joke!


I intended to read all the pages you posted before giving an answer, but I stopped reading after "Let it be assumed that the conditions of heat transfer, flow resistance and flow dynamics are not significantly influenced by skip cycling". Yeah, right. That may be true in engines that solely depend on a scavenging pump. But ours don't; they depend on exhaust resonance. And when you skip just one combustion cycle, the dynamics collapse and so does the next scavenging event. And the next. And the next, until eventually there is enough mixture in the cylinder for successful ignition again.

That's the way I operate too, Neil. Who wants to be rich? I'm happy each time one of my wild ideas actually works.
The Ryger situation is an exception because there is more involved than just my own ideas.

Too bad I wasn't aware of your intentions Jan; I would have been happy to play ball. But don't feel bad about the bouncing PM. I blocked PMs on all public forums; forums absorb far too much of my time as it is, every day.


I didn't do 30k in 6th gear Ken; not on the stretch of road you saw in the picture. There were protruding manhole covers in the middle, leaving a useful width of one kart width plus maybe 30 cm.
Re the catch can filter: I am not even at liberty to confirm that it is a catch can filter, but I will admit that it is a filter. Satisfied? Didn't think so. Nice try though :msn-wink:.


Are you thinking bread crumbs or 36-24-36? In the latter case I can sympathize with you.


I've said this before: it's not up to me to decide which questions regarding the Ryger engine I can or cannot answer.


We're on the same page Husa. The Rygers amazing power and its willingness to rev are not even its main strong points. Its fuel economy and clean exhaust are.
But the environmental climate is not favourable for two-strokes.
Several dutch cities are contemplating a ban on small two-strokes because they are big polluters. Which is true because these 50 cc mopeds and scooters are limited to 25 or 40 kmh. They are not allowed to produce anything like decent power, so their combustion is mediocre.
The logical error is of course that vehicles should be banned if they pollute, not because they are chinese, or orange, or two-strokes. But try telling that to a politician.
The only thing they understand is what the public wants to hear. They don't want to see 'clean' and 'two-stroke' in the same sentence.


You guys ask me if I can answer your questions. The answer is: yes, I can :devil2:.

(OK, the Ryger is easy to start and idles like a normal 2T. I wonder what this candour is going to cost me; I hope I can settle the matter with some ice cream).


I usually order Malaga (vanilla with raisins soaked in rum) but pure vanilla is OK as well.
Re the idling: good point, Ken. I must admit that up to now I hardly paid attention to the way the Ryger engine idles; we're no idle characters :shifty:.
Pure two-stroking idling in a carburetted engine is nearly impossible to achieve. Igniteability (is that english?) requires a certain minimum quantity and quality of cylinder filling, which in turn will lead to 'too much power'; the idling rpm will be so high that you can't really call it idling any more. For HC-free low-rpm idling you'll need skip-cycle direct injection. But I need not tell you that, coming from Orbital.
We can however have an idling that sounds like two-stroking if the engine is evenly four-stroking or six-stroking. Much depends on the position of the spark plug.
I used to race a big two-stroke single with a choice of plug positions and although it had next to no influence on WOT power, there was a remarkable difference in idling behaviour between a central and an offset plug.


All credit for the Ryger engine should go to Harry Ryger, and Harry alone. I'd post a picture of the engine's spiritual father, but Harry prefers to stay in the background. Finding his photo on the world wide web may prove to be as difficult as finding the Ryger patents :p.


One remark in advance, which regards not only the above question but all questions: unless I say otherwise, all my answers concern conventional engines; they may or may not be valid for the Ryger engine, so don't go jumping to conclusions.

Breezy, a good exhaust system triples the power of a racing two-stroke. How would you use that power elsewhere? By driving a compressor for example? It would help but it's not allowed in most types of motor sport. And in case you mean the amount of energy contained in the exhaust gases: I don't see a way of utilizing that other than in the exhaust pipe.

Re dwelling: a short con rod will cause a higher piston acceleration near TDC and a lower acceleration near BDC, so the piston will dwell longer around BDC.
Assuming the cylinder remains unchanged, a shorter rod will increase angle.areas. For example, The Aprilia RSA has a blowdown angle.area of 14322°mm² and a transfer angle.area of 109969°mm². If we replace its 120 mm con rod with a 100 mm rod (17% shorter), the blowdown angle.area becomes 14609°mm² (2% more) and the transfer angle.area becomes 113119°mm² (2,9% more). The drawback is that the short con rod causes more piston friction and costs crankcase volume.


Yes Sonic, it was dyno tested. Yes Husa, he did have biscuits; they were chocolate-clad.


No need to die first in order to become a spiritual father, Breezy. Harry Ryger is alive and kickin' the two-stroke community.

Your logic leaves something to be desired Yow Ling, just like the wifi on the Sachsenring circuit, where I spent the past couple of days, left something to be desired.
I didn't go quiet by choice, mate.

The RSA indeed had steps at top and bottom of the cylinder/manifold junction; something to do with evolution I'd say, like why men have nipples. But I am with Wobbly on this one.
Moreover, the RSA's exhaust port shape as it has become known through the numerous pictures, is not the latest version; the final version had the port floor raised even higher.


I can see there are several great minds at work here. No doubt you could design a triple-overhead desmodromic five-stroke with threedimensional variable valve timing, but keeping things simple seems to be more difficult than that.
I hope you will permit me to use the above quotes when I ever get around to putting the Ryger history in book form, so we can all have a good laugh, looking back on it.


Like I said, I did not do a parts count, but I posted the parts list, so be my guest if you feel so inclined, Jan.
I wrote 98% to give an impression of the simplicity of the modification, but maybe it's only 90%; who cares.


When Facebook announced they would disrespect all privacy rules as of 01-01-2015, I stopped logging in, so I haven't got a clue what is going on there nowadays.
I do know that avoiding facebook saves me over an hour, every day, so I do not intend to go back there.
Who wrote the lines you are quoting? If it was Harry Ryger, you can take his word. And yes, the power, the revs and the emission values are all from the same engine.


Could you let us know what those are, before I answer that I'm not at liberty to answer?


I know what you mean Yow Ling. I felt exactly the same until I got some hands-on experience with the Ryger.


I know the feeling Neil. I'm very glad to be involved with the Ryger engine, but it has also made me very reluctant about everything I thought I knew about two-strokes.


You're right Jonny. I'm able to answer that. But I'm not allowed to.


Could you say how the underside of the piston would shut the exhaust port off at any position, Neil?
We did some playing around with this type of piston too, but it's no good for a two-stroke.
313705

Let alone the things you are about to find out about people in R&D departments. They don't change tyres. None of them (in the glory days when Aprilia was ruling the roost in the 125 and 250 cc classes, there were not 100 but 150 people working in R&D).
Taking care of the tyres was the responsibility of the racing teams, that were completely separate from the R&D dept. And they didn't change tyres either; they just dropped the wheels at the Dunlop, Michelin or Bridgestone service trucks, went for a glass of Lambrusco a cup of coffee, and picked them up again.

When I first heard the numbers, I was very sceptical. When I first got acquainted with the engine, this was my reaction:
http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130866554#post1130866554
There was no need (but a huge desire) to double-check the feeling of that first ride.

You may have to farm out some of the work, but you will be able to keep using most of your current parts.


Are you pulling my leg Ken? When I wrote 'everything I thought I knew about two-strokes', I meant two-strokes. Is there any other kind?
I think I know what you wish to hear. The laws of physics haven't changed but I am beginning to realize that I neglected some aspects of the gas dynamics in an engine as being unimportant, until Harry Ryger showed what can still be found there. I'd really love to be more specific, but that will have to wait until I get the green light.


I happened to notice this addition to your original post, Neil. Normally I would have missed it. And I hate missing things, so from my point of view it would have been safer to put it in a new post instead of adding it to a post that I already thought I'd seen. Come to think of it: God knows how many valuable additions I've already missed because I usually don't go back to 'old' posts.
That Husqvarna video of yours reminds me of a Stihl patent ( http://www.google.com/patents/US6415750?hl=nl&dq=two-stroke+%2B+engine+two-stroke+OR+engine ) wherein scavenging is also taken care of by air only, after which the fuel-air mixture is transferred. But I don't see any similarities with the Ryger engine.


I never planned to control the exhaust ports. We talked about controlling the transfer ports here (via the 'commas') but once Flettner showed an interest, I thankfully turned my mind to other (Ryger) things.


It may be just my suspicious mind, but do I feel a hand on my leg again?

It starts like any other kart engine. You get a push, you knock the shift lever into second gear and off you go. And I don't need to tell you that any conventional two-stroke is started with the help of a positive mechanical displacer for the incoming gas or air: the crankcase pump. That's all I can say right now.


I don't think the non-disclosure agreement applies here, but a normal chat between friends also deserves some privacy, so I won't give any details, but Harry intends to supply his own engines. He's not in it for the money, he's just a guy with a passion for two-strokes, just like yours truly.


Not on me, Neil.
The flywheel is the critical part. I can't remember which steel it was made out of, but the flywheel and both shaft stubs were made out of one lump. No holes, no shrink or press fits, no welding or glueing. The centrifugal tension concentrates on the center and if there is a hole there, you lose 50% of the permissible tension.


Some more pictures of the dyno:
313816 313815


True. Measuring with test props will you give just one point of the power curve per measurement; your engine will be worn out before the curve is completed.

Pressure measuring gives you the pressure at a given distance from the exhaust port, at a given point in time. With pressure waves coming and going in both directions, chances are that you are measuring maximum or minimum wave superposition values, or anything in between, which will only teach you to dedicate your time and energy to other aspects of the engine.

Engine size does not figure in resonance phasing. The MB40 engine has 190°/130° timing, like you would expect from any decent two-stroke.

I don't recall the rotary inlet timing of the hollow crankshaft shown below but it will probably be something like 140°/60°. That may seem tame and it is; this is not a high-revving engine :msn-wink:. It doesn't exceed 35000 rpm and then the mean piston speed is only 23 m/s. Compare that to 26,3 m/s for an Aprilia RSA (or 54 m/s for a Ryger).
Anyway, I feel that this kind of shaft rotary inlet for model engines is a fashion thing more than anything else; I wouldn't be surprised if simple piston port induction would perform better (it would certainly flow better).
313817


Good thinking Peewee. All hell broke loose here because of the Ryger homologation confirmation so I can't find the time to write a decent explanation, but here is a picture of the RSA's A-duct geometry where you can see the inner and outer radii and the coordinates of their centers.
314338


The international homologation for the 125 cc Ryger kart engine was accepted yesterday. The Federation Internationale de l'Automobile typically needs six weeks to put their paperwork online,
but I will try to make the complete document available later this week.


yeah right :laugh: they should switch to electric powered karts with solar charging then. From the ppm values I saw from the ryger engine, it is not as good as a four stroke, yet, let alone a four stroke with catalytic converter. (If a four stroke can be anything like "good", that is.)



By the way, thanks for the above explanation, I got it now. On the VHM website I saw a combustion chamber which was nicely shaped to follow the piston dome with the radiused edge. But that was a design which protrudes into the bore. So I think I can now safely try radiusing, too. Before I saw that picture, I was always afraid that the outside of the dome might distort and provoke detonation.


And with quite a fine mesh, too! Sometimes I miss all the tools I once had at my disposal. Did they use 3D CFD at Aprilia? Personally, I don't think that's necessary in race engine development, but it sure is a nice help in visualizing the scavenging (and, more importantly, visualizing the differences in scavenging between two variants).


Ryger production is running in high gear in order to meet the CIK regulations.
314432314433


Love the idea. And if you compare the size of a Ryger two-stroke single with a Moto3 foul-stroke engine, you can imagine how beautifully compact that V6 could be.
And imagine the sound of it! Bernie Ecclestone has been complaining about the lack of audio attraction in the present F1 turbo engines. An unsilenced Ryger V6 revving to your heart's desire could easily make that complaint go away.
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You could make the financial aspect of the non-disclosure agreement go away. But that is not what it's about. I gave my word, simple as that.
Maybe you could spend your money trying to make Ecclestone see the error of his ways when he said "no two-strokes in F1".

don't you love it when you can use the same text twice Wob?


Thanks Wob. What's your poison?
You're quite right about the ignition. In fact the Ryger prototype has been running all year with the CIK-homologated fixed-advance PVL ignition.


Frits has categorically said several times that the 125 kart engine makes 70 Hp @ 17K and revs to 30,000.
And he is a man I respect - who wont say what he isnt allowed to, but for sure I believe what he does actually say.
The homolgation application papers show the bore/stroke and rod length for that single cylinder 125 engine he
has been talking about.

That engine if it gets passed by the CIK it must run the homologated PVL analogue ignition with all but a straight line advance curve.
I have test bench graphs from PVL that show plenty of ignition power up to 20,000 so maybe its OK at another 10,000.
It must be as Frits has driven the thing at 30,000 in reality - havnt you been watching.

Whoops Wob i indeed missed where Frits said it revved to 30000 when he drove it.
but i have bolded it and the 54ms.

[Frits Overmars]

The idea of the double pumping was more to allow continuous induction it would alternately breath through the upper and lower in turns .You're not getting off this easily, Husa. Let's assume your lower chamber breathes from atmosphere. Then the upper chamber won't, because it gets all it can swallow from the lower chamber; no continuous induction from the atmosphere.


In practice the under and over pumping would be pumping no more that the actual capacity of the cylinder wouldn't it? so technically legalish.With double-pumping each stroke would theoretically inhale one cylinder capacity; that's twice the cylinder capacity per crankshaft revolution; illegal as hell.


If the mixture was compressed, wouldn't it be able to flow faster buying valuable time.Flowing through the transfer ports, yes. But flowing from one chamber to the other? What good would that do?


Bugger the rules they are made by four stroke people anyway.These days they own the playing field, so we'll have to get through the gate in order to beat them.

[RAW]

Hmm, I thought I had missed the 30k rpm bit also. Cheers Husa, plenty of those rotors have issues when being reved quite high, 30k is well in excess of quite high, good luck, I'm more than happy to learn.

[husaberg]

You're not getting off this easily, Husa. Let's assume your lower chamber breathes from atmosphere. Then the upper chamber won't, because it gets all it can swallow from the lower chamber; no continuous induction from the atmosphere.

With double-pumping each stroke would theoretically inhale one cylinder capacity; that's twice the cylinder capacity per crankshaft revolution; illegal as hell.

Flowing through the transfer ports, yes. But flowing from one chamber to the other? What good would that do?

Yeah, at the moment they own the playing field, so we'll have to get through the gate in order to beat them.

I might have to badly draw a picture.
The muddled thought I have is it breaths into the lower chamber and the upper one in turn through a bifurcated reed.one half the v to the top one to the bottom
the upper and lower chamber communicate with a flat plated Suzuki like reed allowing flow in the upwards direction only.
when the Richard Maas drawing is at bdc the pumping chamber underneath is fully open. when the piston is at TDC the lower chamber is fully closed. but the upper one is fully onpen the rush of the air into the top pumping chamber should also allow additional air to be drawn into the upper pumping chamber.

But yes it might be very supercharged (a little) but it needs to fill all those transfers as well.:lol: my gut says that by the time the volume of a ring of transfers were added up it would be not much above atmospheric pressure.

But yes it also fails KISS. I guess with the Richard Maas drawing, it still allows near continuous flow into the transfer and the Ryger look like it does breath near direct into the transfers.

[Lightbulb]

This is all very interesting what people are coming up with ideas wise.
Lots of stuff to get your head around for sure.
Neil

[JdG]

Something like this Husa?

Shitty drawing (in dutch) I know, but I think you're thinking what I was thinking that you were thinking :yes:

[JdG]

I also didn't take the time to rotate the picture 90 deg. clockwise.

Sorry...

[Frits Overmars]

Something like this Husa? Shitty drawing (in dutch) I know, but I think you're thinking what I was thinking that you were thinking This is double-pumping:2guns:, this is illegal :Police:, and this really works :niceone:.

[136kg136ps]

That ruins my idea then as well.I had thought there might be a flexible boot or membrane that separated the cylinder from the crankcase and being attached to the connecting rod provided a boosted mixture.Also very common in some types of pumps to use reeds to control flow.But if that is illegal obviously we go back to the drawing/guessing board.

Good luck in the patent process BTW!

[Lef16]

I remember that wob said once about the Aprilia's big tranfer duct divider.He said that flat sharp divider is old school and doesen't fit to modern racing engines.
But apart from the divider,I also have a question about the boost-C port,which is very small in the entry area,and if I remeber correctly it has 1.1:1 entry-exit ratio,A has 1.3 and B has 1.2,am I right?
Why karts use this style of porting instead of Aprilia-style?

[Flettner]

The riddle of the ryger, a free piston engine will oscilate at (30,000?) with no rod or crank. How does the piston not end up in a big heap at one end? Gas compression absorbs the inertia each cycle. In the ryger, if the pumping chamber ( formally called the crank case ) pumped down to a "squish" this would do two things. 1, unload the normal piston deceleration load on the conrod and 2, create the high pumping pressures required to charge a not fully blowen down cylinder but the amount of gas transfered would be limited, perhaps why fuel air does not get out the exhaust. With lots of small transfer ports control over gas positioning in the cylinder would be more accurate.
To make 70hp with a 30mm carb, it would have to be passing air all the time not gulp filling like a normal engine, soooo if we had say four smaller transfer ports either side of the cylinder feeding from the high pressure under piston pump (eight transfers) and we had three more at the rear of the cylinder that are piston ported to fill the high pressure under piston pump (at TDC) but also the same ports when the piston was at BDC feed straight into the cylinder, helping to make up for the lack of volume delivered by the high pressure under piston pump. Air fuel would be drawn in when the piston was on the way up and also when the piston is nearly down. With gas inertia and some funny looking "thing" inside what we thought was the intake reed, that helps retard back flow (not a reed), flow through the carb would be fairly constant I imagine.
I think the exhaust expansion chamber would not have a very steep reverse cone but internal system pressure would have to be fairly well controlled?
Imagine that

[adegnes]

The riddle of the ryger, a free piston engine will occilate at (30,000?) with no rod or crank. How does the piston not end up in a big heap at one end? Gas compression absorbs the inertia each cycle. In the ryger, if the pumping chamber ( formally called the crank case ) pumped down to a "squish" this would do two things. 1, unload the normal piston deceleration load on the conrod and 2, create the high pumping pressures required to charge a not fully blowen down cylinder but the amount of gas transfered would be limited, perhaps why fuel air does not get out the exhaust. With lots of small transfer ports control over gas positioning in the cylinder would be more accurate.
To make 70hp with a 30mm carb, it would have to be passing air all the time not gulp filling like a normal engine, soooo if we had say four smaller transfer ports either side of the cylinder feeding from the high pressure under piston pump (eight transfers) and we had three more at the rear of the cylinder that are piston ported to fill the high pressure under piston pump (at TDC) but also the same ports when the piston was at BDC feed straight into the cylinder, helping to make up for the lack of volume delivered by the high pressure under piston pump. Air fuel would be drawn in when the piston was on the way up and when the piston is nearly down. With gas inertia and some funny looking "thing" inside what we thought was the intake reed, that helps retard back flow (not a reed), flow through the carb would be fairly constant I imagine.
I think the exhaust expansion chamber would not have a very steep reverse cone but internal system pressure would have to be fairly well controled?

Clever indeed.

[wobbly]

There are a few clever enough people ( like Holzer at Modena ) working on kart engine design that I am sure enough R&D has been done to establish
if the basic ideas behind Jans Aprilia scavenging works "better" than the current monkey see monkey do Hondarish arrangement.
Problem is that we are dealing with a very different apple to the GP Aprilia.
It has a power valve and a mile of clever electronics - a KZ2 has neither.
I have replicated the actual port timing layout ( lower but with B,C opening first ) and this makes considerably better power
from peak onwards,but what it gains in overev it looses way more down at 9000.
This is the rpm when exiting the slowest hairpins ( usually only once per lap ) but it is just way too slow at this point that lap times suffer excessively.
I also have replicated the Aux ports ground around to bore centre, and this also makes a HUGE gain in overev power and useable rpm.
But in this case it looses some 1.5 Hp at 9000, and this can be got back with plugs in the small end pin.
This loss is easily offset by the fact we can add another tooth on the back and rev it alot harder ( 15,000 ) - lap times drop,so that is a worthwhile gain.
The extra rpm available also allows deleting several between corner gearchanges, again making faster lap times.

The other problem is that it is a big mistake to assume that simply replicating one small element of Jans concept will be a positive step for any old port arrangement.
I know others have tried to add material to the B duct front face, making the wide septum entry, but this then completely changes that front walls entry angle into
the cylinder - and this for sure is doomed if the whole reverse stagger,axial angles scenario etc etc isnt used as well..

[husaberg]

Something like this Husa?

Shitty drawing (in dutch) I know, but I think you're thinking what I was thinking that you were thinking :yes:


This is double-pumping:2guns:, this is illegal :Police:, and this really works :niceone:.

I couldn't find the crayons
314679



The riddle of the ryger, a free piston engine will occilate at (30,000?) with no rod or crank. How does the piston not end up in a big heap at one end? Gas compression absorbs the inertia each cycle. In the ryger, if the pumping chamber ( formally called the crank case ) pumped down to a "squish" this would do two things. 1, unload the normal piston deceleration load on the conrod and 2, create the high pumping pressures required to charge a not fully blowen down cylinder but the amount of gas transfered would be limited, perhaps why fuel air does not get out the exhaust. With lots of small transfer ports control over gas positioning in the cylinder would be more accurate.
To make 70hp with a 30mm carb, it would have to be passing air all the time not gulp filling like a normal engine, soooo if we had say four smaller transfer ports either side of the cylinder feeding from the high pressure under piston pump (eight transfers) and we had three more at the rear of the cylinder that are piston ported to fill the high pressure under piston pump (at TDC) but also the same ports when the piston was at BDC feed straight into the cylinder, helping to make up for the lack of volume delivered by the high pressure under piston pump. Air fuel would be drawn in when the piston was on the way up and also when the piston is nearly down. With gas inertia and some funny looking "thing" inside what we thought was the intake reed, that helps retard back flow (not a reed), flow through the carb would be fairly constant I imagine.
I think the exhaust expansion chamber would not have a very steep reverse cone but internal system pressure would have to be fairly well controlled?
Imagine that
I think that is pretty much it.
No sim that covers rpm potential will work as the sim likely does not take the cushion into effect of its accepted parameters.

https://www.highpowermedia.com/blog/3414/mmc-finds-more-motor-sport-applications

[peewee]

frits maybe you can offer some help. i followed your theoretical exh shape with top radius at 75% and corner radius at 8.1% and got whats show in the pic but when i try to draw it on paper i end up with less than 13.7% vertical half axis. around 12% is what i get. do you think im making a error somehow when i draw it ?

actually now i think about it, my exh width might of only been 65% of bore and thats where the error is. since your theoretical exh is based on a 70% wide window, do you have a guess what the roof and top corner radius should be for a 65% wide window and vertical half axis ?

[wobbly]

OK, with a bunch of serious patent searching ,I think we have a handle on the stepped piston multi transfers with close coupled reeds
in the plate scenario.
But no one has even come close to the safe at 30,000 bottom end.
Tear your hair out you fuckers, till we get this sorted we really are tossing into the wind.

[Flettner]

OK, with a bunch of serious patent searching ,I think we have a handle on the stepped piston multi transfers with close coupled reeds
in the plate scenario.
But no one has even come close to the safe at 30,000 bottom end.
Tear your hair out you fuckers, till we get this sorted we really are tossing into the wind.

I got my bottom end sorted:laugh:
I'll post a before and after, after being, picking all the bits up from where they spreed themselves round the yard :eek:

[Frits Overmars]

frits maybe you can offer some help. i followed your theoretical exh shape with top radius at 75% and corner radius at 8.1% and got whats show in the pic but when i try to draw it on paper i end up with less than 13.7% vertical half axis. around 12% is what i get. do you think im making a error somehow when i draw it ?
actually now i think about it, my exh width might of only been 65% of bore and thats where the error is. since your theoretical exh is based on a 70% wide window, do you have a guess what the roof and top corner radius should be for a 65% wide window and vertical half axis ?Let's assume a port width of 65% of the bore. Then you can calculate the vertical half-axis yourself; that is why I posted my port shape concept in the first place.
314714
The minimum safe vertical half-axis becomes
0,7 x (port width / cylinder bore)^4,57 x cylinder bore
= 0,7 x 0,65^4,57 x cylinder bore
= 0,09775 x cylinder bore

Converting this half-axis into center and corner radii can't be done with a simple formula, so I'll do it for you, once-only.
center radius = 88% of bore
corner radii = 5,2% of bore

But wait, there's more.
From your screenshot:
exhaust port height from top = 47,0 mm
exhaust port window height = 30,7 mm
You didn't stipulate the cylinder bore, the stroke and the conrod length and I don't fancy searching through the forum to see whether you gave them before, so I'm going to assume the values I need:
stroke = 77,7 mm
con rod length = 148 mm
exhaust timing = 172°
Now I'll leave it to Wobbly to tell you what to expect...

[Frits Overmars]

I got my bottom end sorted:laugh:
I'll post a before and after, after being, picking all the bits up from where they spreed themselves round the yard :eek:I do hope you were wearing your bulletproof shorts, Neil.

[husaberg]

I do hope you were wearing your bulletproof shorts, Neil.

Is the ryger made of Kevlar..............:bleh:

[PFPRAIDER]

Most of it has seemingly been scrubed from the Internet. It appears to be a mop up and clean excersize. just saying............
http://forum.pyrotherm.rs/forum/index.php?/topic/4015-ryger-engine-125cc-30000-rpm-70-bhp/page__pid__91798
Pretty sure it is not 30000 RPM though maybe the rev counter is in lira?
There seems to be a mention of it in the Search for this page but maybe only for Friends. bet lozza is a facebook friend of his though
https://www.facebook.com/luc.foekema/media_set?set=a.1761099246360.71824.1805454134&type=3Special
Again? the same info
http://www.rygerengine.com/index.emissions.htm
its all German to me.......

http://www.rygerengine.com/
I had another page but I can't find it (I think I looked under cached pages)
....... have you looked on pitlane Ken?
I do know how to find obsolete and deleted information.. but not tonight.
Frits will be along soon to explain all.......... LOL


I haven't either?

Marketing
Create a buzz
Peak peoples interest
Limit information available.
What better advertising than word of mouth.

Just saying...........


Hi Guys if you look carefully you will find it must have a very long piston as the CIK Fiche shows it only has a 90mm long rod. Sorry spelt Ryger wrong in title,
just noticed you had all ready mentioned all this earlier.

[adegnes]

Was reading trough old posts and found this picture:

http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=274855&d=1356057639

Now thats a bucket racer! The front number plate and rear fairing looks to be cut from the same trash can or wathever. Great idea! I think I'll borrow that patent in my pursuit of a more streamlined rear end.

[adegnes]

Is that tail-piece a side cut Bucket? Very nicely done! Top marks.


Yes a bucket for a Bucket. The front number board is the off cut from the bucket tail piece.

Old news, sorry...

[philou]

Trash goes well with minarelli am6 engine

[adegnes]

Trash goes well with minarelli am6 engine

Yep, both Derbi and Piaggio has better more well built alternatives.

[wobbly]

I will wait till peewee sends me the EngMod file to review, as even with only the Ex analysis page on here so far
I can see that the Aux are too high and all wrong in shape anyway.
The Ex by itself is pretty irrelevant till the transfer height is part of the analysis to generate the blowdown number.