ESE's works engine tuner

[Lightbulb]

A random Ryger thought. Now, if a KZ has peak power @ 13k and the Ryger is @17k and it uses the same exhaust, this got me thinking. On the basis that Harry is still using the exhaust to improve the trapping efficiency then, all things being equal, could this mean that the exhaust duration is 13/17 ths of the normal KZ of, say 190deg, giving a duration of 145 deg? One thought is that this could give a longer power stroke. However, it also must be recognised that if 30% of the fuel energy goes equally to the power, coolant and exhaust, then we have 70 hp at our disposal to do something with, maybe in a more efficient way that just energising the exhaust system.

Obviously the line of thought is that, on the basis that the exhaust opens later, some other ports/passages open earlier to provide some subsequent mixture mass flow assistance. It is stated that there are 11 transfers. Looking at the pics, it does look like, externally anyway, that there is the conventional 2 *A, 2*B and 1*C, ports. So, the other six "transfers" might still be transfers, but carrying some flow in the downwards direction. There is no spec in the CIK regs that specify a bulk flow direction within the transfers.

Ken, you think my guess might be fairly close then.
I recon the other ports are not transfer ports, but are most likely induction ports of some kind before it is super compressed. As it is simple and yet very different, this makes more sense to me.
Early successful schnurle ported model diesel race engines had Transfer timings of 90 to 100 deg and exhaust timing of 110 to 120 deg. The models flew 3.3km on lines at about 190km/h on 6cc of fuel/ 1 max tank capacity. The newest ones have case designs where they have made the cases with the least amount of volume possible,but have ex timings in the 140 to 150 range and transfer timings in the 115 to 125 deg. They now do 210 km/h and 5.1 to 5.2 km/tank /6cc max fuel. So they have dramatically improved efficiency and still do not use tuned pipes. If the Ryger does not need a crank case to flow air fuel into the engine, there is the possibility to get substantially higher transfer pressures and a pipe design that only does the efficient extraction of the exhaust and supplies only enough total system pressure to keep the maximum amount of air fuel in the cylinder.
Neil

[sonic_v]

A random Ryger thought. Now, if a KZ has peak power @ 13k and the Ryger is @17k and it uses the same exhaust, this got me thinking. On the basis that Harry is still using the exhaust to improve the trapping efficiency then, all things being equal, could this mean that the exhaust duration is 13/17 ths of the normal KZ of, say 190deg, giving a duration of 145 deg? .

Ken

You have got your ratio the wrong way round. The duration would be 17/13 times 190 giving 248 degrees duration.

[PVO]

The ring is stationary, no inertia no matter what speed. Gas pressure would still be able to squeeze the ring in, like normal just the other way round, could even be small holes from combustion chamber to the back of the ring? Maybe. Ring would have to be well supported so it can only move in "a knats cock" smaller than the piston when the piston is not there. Could it be any worse than in our normal engines with the ring bulging out of its groove every time it passes the exhaust port. Twice every cycle the ring has to be shoved back into it's groove by a small champher in the exhaust port, the ring in the side of the cylinder wall would have to move less than that. Latest ring technology has it that there is not much spring pressure (movement) in the ring when its loose on the piston, out of the cylinder. I know it sounds crazy but what else?
If the rings never touch the piston, then they are not piston rings

Based on this photo of the Ryger after testing it looks like the ring may move with the piston. Note the undisturbed cross-hatch at the top of the cylinder bore. Around 10mm down you can see the wear line where, presumably the ring changes direction. If the piston moves straight up and down I would not expect this wear to come from the piston contacting the cylinder.

The alternative would be that the piston does contact the bore due to expansion. If this were the case then perhaps a ring isn't used at all. These are just a couple observations I've made, which may or may not have any merit.

Figuring out how to use gas pressure to float the ring in the piston groove throughout the engine's stroke would be clever.

Or perhaps you run ring-less with a tight fitting piston and use a high compression ratio. Then put whatever gases that escape past the piston to use on the next cycle.

Paul



Image Source: Knowledge FB

[F5 Dave]

A stepped head like a gg or others would explain the hone marks. What is the std kart head design?

[wobbly]

Your average KZ2 has the squish spigoted down 3mm + 1mm squish +2.5mm ring land.
So the ring is stopping in that bore at the same place.

As we know that the volume of fuel/air that is inducted into the cylinder on each stroke is actually residing in the transfer ducts (NOT in the case ) then if
those transfers are connected to a very small volume under the piston ( and insulated from the crankcase ) then that volume will be affected by a VERY high piston
compression ratio as it drops - before the ports open.
Thus the induction system only has to supply mixture into a space that comprises mainly of the transfer volume itself.
Fast to fill due to the small volume, fast to empty due to the compression ratio, and much less reliant on pipe effects around bdc to evacuate the cylinder.

If the ratio of transfer port STA is then matched correctly to the Ex STA to optimize this system then high efficiency would result.
But we have been told the ports timings are relatively unimportant, thus I believe some derivative of the FOS radial ring of transfers setup with that small connecting volume is acting
to create a very coherent vertical tower of Pisa effect.
It is this that efficiently evacuates the whole cylinder ,and this would explain the port timing comment exactly.

But we still have no idea of what is hiding in the crankcase.

[Flettner]

Based on this photo of the Ryger after testing it looks like the ring may move with the piston. Note the undisturbed cross-hatch at the top of the cylinder bore. Around 10mm down you can see the wear line where, presumably the ring changes direction. If the piston moves straight up and down I would not expect this wear to come from the piston contacting the cylinder.

The alternative would be that the piston does contact the bore due to expansion. If this were the case then perhaps a ring isn't used at all. These are just a couple observations I've made, which may or may not have any merit.

Figuring out how to use gas pressure to float the ring in the piston groove throughout the engine's stroke would be clever.

Or perhaps you run ring-less with a tight fitting piston and use a high compression ratio. Then put whatever gases that escape past the piston to use on the next cycle.

Paul



Image Source: Knowledge FB

Yes it certainly looks that way, if this is the 70 HP cylinder. It might well be that the ring is somthing completly not what we think a ring should look like?

[peewee]

hey guys im going to start a yamaha project pretty soon and split my time between it and finishing this ktm project. luckily i learned alot about welding just in the last few months on the ktm, as this yamaha will have some welding also but not near as much as the ktm. i got some ideas to accomplish things such as raising the exh floor with far less welding and heat warpage so i hope they work out like i think. once i get going ill have some pics. anyways i just wanted to see what my welds looked like today in comparison to a few months back. hopefully i can continue to learn even more as i find welding quit a bit of fun. blob of shit on the left was few months ago and the bead on the right is from today

[JanBros]

As we know that the volume of fuel/air that is inducted into the cylinder on each stroke is actually residing in the transfer ducts (NOT in the case ) then ...

... you are still thinking inside the box and not outside, which in a lesser or more degree we need to do ?

which doesn't mean you are wrong, only saying it might not aply to the Ryger

[TZ350]

Are you trying to copy my sleek design!?

Attachment 315045

I love it.

i just wanted to see what my welds looked like today in comparison to a few months back.

Thats good welding.

https://youtu.be/NjHr6_8hEqc having been inspired by TZ and this thread . finally got this running. suzuki gp 125 crank, cagiva mito barrel, bsa bantam cases. had originally used rotax junior barrel but changed for the power valved mito barrel because of the 50.6 x 56 stroke and bore.

Looking good, a fast BSA Bantam ....

The first bike I ever rode was a Bantam, fell off it at the first corner.

[ken seeber]

Ken

You have got your ratio the wrong way round. The duration would be 17/13 times 190 giving 248 degrees duration.

Sonic, you're right. Well spotted. Have to rethink things again. At least I can blame something....old age.

As to the pics posted on Knowledge, there is something amiss. The pics show a cylinder with a face O ring seal, whereas the Ryger and VM have a deep counterbore around the OD, where in the case of the VM, the head spigots into the counterbore bore with a O ring sealing against this bore. Also, the Ryger cylinder bore pic we have seen shows an unmarked piston crown, with coarse machining, whereas the the pis shows a Mondokart branded piston, which is in fact originally a Meteor piston.

[SwePatrick]

What if..

All that´s been said about this Rygerengine is just smoke and mirrors?
Carefully planned infoleaks to build up some rumors that increase from mouth to mouth, and gain 'mythstatus'.
And in the ending isn´t more than a 'longrod' twostroke?

With that said,, there aren´t really anything to discuss.
We´ve seen a cylinder with a piston halfway down.
and an outside picture with an 'old' setup cylinderreed config raised with a spacer.
Some 'paper's' that can have been printed out with some fantasy in photoshop.
A picture of some suspicious hoses and bottles mounted in a kart.
some statement like 'do not let the piston touch the rings', yes... what rings?
O-ring that seal cylinder?
It doesn´t state in detail what rings.

And finally,, let´s just wait and see.
Good things come to those who waits.

Rgds

[Lightbulb]

What if the pipe is no longer a tuned pipe when connected to a Ryger engine. Then the timing numbers do not matter any more.
Fairly hard to tell, but if the piston is 1/2 way down the bore and the ex is still not open, then I might be on the right line of thinking.
Neil

[Flettner]

What if..

All that´s been said about this Rygerengine is just smoke and mirrors?
Carefully planned infoleaks to build up some rumors that increase from mouth to mouth, and gain 'mythstatus'.
And in the ending isn´t more than a 'longrod' twostroke?

With that said,, there aren´t really anything to discuss.
We´ve seen a cylinder with a piston halfway down.
and an outside picture with an 'old' setup cylinderreed config raised with a spacer.
Some 'paper's' that can have been printed out with some fantasy in photoshop.
A picture of some suspicious hoses and bottles mounted in a kart.
some statement like 'do not let the piston touch the rings', yes... what rings?
O-ring that seal cylinder?
It doesn´t state in detail what rings.

And finally,, let´s just wait and see.
Good things come to those who waits.

Rgds

I agree, but Fits gives it the stamp of approval, hard to ignore!
Running without premix (oil to the top end) also hard to ignore.
Good things come to those who wait, can't wait, how long will it take?

[wobbly]

Yea well I said exactly what SwePat is saying months ago, but unfortunately it is a confirmed fact that the Ryger has applied for
a official homologation with the CIK - this is NOT smoke and mirrors.
It HAS NOT been approved ( the application has only been approved and then forwarded by Rygers country ISN associate of the CIK ) but the homologation is in process as we speak.
And yes I insist that having a very low Ex duration, would in fact allow the engine to use a normal style pipe but then use superposition to give
huge gains in power at the rpm extremes.
We have seen a pic of a very normal looking KZ2 pipe, but for sure from the visual I can see the rear cone is reduced in taper, thus naturally allowing greater powerband width.

But to give big gains in emission control as well as big gains in power there are only three variables that matter.

First is scavenging efficiency, and as we know it has a huge number of transfer ports, then it logically follows that if these are directed properly
we can assume that it generates a very high proportion of clean A/F in the cylinder at the point of combustion - helping both power and emissions.

Next is trapping efficiency,this I would suspect is a natural result of having a very low Ex duration, as the cylinder is being quickly filled by that superb
scavenging regime with pure A/F mixture, then most of it is then held within the cylinder with little chance to escape into the duct and pipe.

Lastly is charging ratio,to make more power it is a simple corollary that we need MORE A/F mixture to be ingested per revolution than simply the swept
volume created byf the bore X stroke calculation.
Again , this is a natural corollary of having a huge transfer STA created by the multiple ports needed to give the great scavenging regime.

If we then add the other elements that seem to be making everyone tear their hair out ie no ring friction,and the ability to be reliable at 30,000 rpm
then this man Harry Ryger may just replace my current 2T hero, no sweat.

[Grumph]

Can i suggest that as the Ryger homologation form says two rings, there are indeed two rings...Possibly one in the conventional position close to the top of the piston, and the second at the bottom.

If it indeed has a lower end carrying oil as seems to be accepted now, a lower ring is pretty well essential to prevent oil migration to the combustion chamber.

If it is not using the crankcase as part of the induction process, the piston can be a very plain, symmetrical shape with no lower cutaways.

If the piston is longer than we would currently accept as normal, the pin boss could be relatively low, leading to the use of a shortish - 90mm - rod which could be quite nuggety - fourstroke proportions...

Lot of ifs.....

And how you prevent the ring touching the piston - or why you would want to, I don't know.