ESE's works engine tuner

[TZ350]

Good spotting, thanks. ..... :niceone:

[philou]

Does it sell?

http://www.moto-station.com/actualites/wp-content/uploads/2014/07/ronax_500_profil-500x375.jpg

[peewee]

The case com ratio is a very important element, guessing or not measuring it correctly isnt an option.
PS - you have a worn out piston available, drill a hole in it.

that's what I did driiled a hole in a old piston. seems like a also packed modeling clay on the inside of the reed block and then bolted it to the cylinder. might of even packed alittle clay in the exh ports at the bore face so oil cant excape out exh between piston and bore. watch for any air pockets as it will throw off your results

[peewee]

My buttugly racer has met some development in the looks ;)
A couple of heatcyckles more and i´ll se what it produces on the dyno.
Everythings new in the engine.
Bearings,crank,cylinder,piston.
I have ported the cylinder som more also.
Switch to methanol has been done.

It has been started since the pic was taken

https://scontent.xx.fbcdn.net/v/t31.0-8/18422456_10154933198924475_7615455308585216370_o.j pg?oh=20ffc18818c6d31efaef3c19f36b336f&oe=59A22D59

nice job there. will you be using standard Kawasaki ign box ? if so can you report back if the best results require the timing plate under the flywheel to be advanced or not ?

[peewee]

Hi Juergen.
Jeah... I also like it a lot, turned out great. Martin sculptured it for me after we agreed on the design, ccs, etc.
Have you noticed it protrudes into th cyl. just like Jan spoke about a few pages ago?

And about the short circuiting caused by strangely designed piston that also came up a few pages ago.
Also encountered this problem with the Gasgas piston.
Decision was made not to open aux. exhaust pass the holed piston sides.
Engmod showed enough TA with 193* exh. duration. 72X72 are relatively big numbers, around 9500 rpm at max power with good overrev was the goal.

im thinking the wiseco ktm300 would be your best bet as far as I know but double check to be sure it will fit your engine. if you notice the front bottom corner in the red circle. the gasgas version might possibly allow a connection from crankcase to exh at tdc so watch for that. this is why I think the ktm version would be more suited. 858M07200 I think is the part #

[jamathi]

How is the Lithuanian 'Rygerised' Honda doing?

[TZ350]

.

Clicked over 4 million hits on the Team ESE thread today, this thread is like some super dinner party with really great friends.

331005

And just like the Queen's great Birthday bash, a big thank you and thumbs up to all the great people who contribute to and read this thread, they all make it a fun and an interesting way to learn something new about 2T's.

[tjbw]

How is the Lithuanian 'Rygerised' Honda doing?

I was thinking about that too.

Paging katinas paging katinas

[husaberg]

How is the Lithuanian 'Rygerised' Honda doing?


I was thinking about that too.

Paging katinas paging katinas


Honda NS 250 -28mm.
Honda NS 400- 26mm.
But these carbs works best with original airbox with foam filter. Anyway so much modification is needed and not just like change main jet, but with emulsion tube, needle, power jet, etc., because no acceleration.
.............................

[Frits Overmars]

Let's switch to four-strokes, they said.
Oil on the track? Nah, won't happen....
https://www.facebook.com/frits.overmars.5/videos/vb.1844833144/10207090352377598/?type=2&theater

[Michael Moore]

FWIW, Jeff Henise and I spent the afternoon machining two TZ350 heads to convert them to replaceable combustion chamber inserts for his Bonneville LSR project.

I did a simple program at the mill and machined the first head and everything went along fine -- not as fast as possible (no flood coolant on my mill) but no excitement either.

The second head was a different story. It either at some point got hot enough in use to completely anneal it or that batch of heads was from a different alloy or HT spec from the first. Nasty gummy aluminum, building up on the cutter to the point of making the head extremely hot from rubbing as well as pushing it out of position (4 clamps, the first head had no problem) 2/3 of the way through the cycle.

It would be interesting to know what was going on. The same end mill that worked a treat on the first one immediately went into "I'm not happy" mode on the second one so we're pretty sure it was the head casting and not anything we were doing (same program as the first head). Slowing the feeds and RPM down by about 2/3 took some of the "why is the coolant smoking so much?" heat out of the head but even with that the EM was clearly pushing metal around instead of cutting it.

I guess it is just part of the mystique of old race bikes.

cheers,
Michael

[wobbly]

Seen that before when the head has been weld repaired.
This kills the heat treat and weld materiel is usually different ( wrong ) as well.

[WilDun]

Let's switch to four-strokes, they said.
Oil on the track? Nah, won't happen....

Now look here Frits, how often do I have to tell you not to watch a "four stroke" race? :msn-wink:



FWIW, Jeff Henise and I spent the afternoon machining two TZ350 heads to convert them to replaceable combustion chamber inserts for his Bonneville LSR project............. The second head was a different story.......... or that batch of heads was from a different alloy or HT spec from the first. Nasty gummy aluminum, building up on the cutter to the point of making the head extremely hot from rubbing as well as pushing it out of position (4 clamps, the first head had no problem) 2/3 of the way through the cycle. ......................was clearly pushing metal around instead of cutting it...........
cheers,
Michael

Not trying to be an expert of course, but it would seem to me that it was cast from a high silicon content ally (good for fluidity in castings), but which is well known for blunting cutting tools and sticking to them (as I have experienced many times over the years!). :brick:

[SwePatrick]

nice job there. will you be using standard Kawasaki ign box ? if so can you report back if the best results require the timing plate under the flywheel to be advanced or not ?

Hello.

Sorry, but i'm using either PVL or Ignitech.

TZ350, glad you like it =)

And,,, no problems in dyno. i built my own ;)

[Michael Moore]

WilDun, the first head machined fine, the second was horrible from the start and I'd be surprised if Yamaha had made a big change in alloy between them. The first one seemed pretty normal to machine for a Japanese casting.

wobbly, I didn't notice any obvious weld repairs on the second one but then I didn't have a reason to go looking for them. Both heads had been nibbled on around the edge of the chambers, perhaps the second head had already been repaired a time or three. Both chambers were like that all the way through, it wasn't a localized spot.

The second head will be the back up that hopefully doesn't get used, but it should be OK as a water jacket with the chamber inserts to the spec you sent Jeff.

It was another typical day in the shop with Mr. Murphy.

cheers,
Michael

[WilDun]

...........I'd be surprised if Yamaha had made a big change in alloy between them. The first one seemed pretty normal to machine for a Japanese casting.
wobbly, I didn't notice any obvious weld repairs on the second one but then I didn't have a reason to go looking for them.
cheers,
Michael

Yes, I don't think Yamaha would have changed materials much and probably aren't responsible - Wobbly could be right, but could it be that someone has made a copy in the past? (we know that lots of people do this type of thing! :msn-wink:).

[jonny quest]

https://www.facebook.com/TwoStrokePerformance/videos/1424363624297601/?hc_ref=NEWSFEED

YZ125 with fuel injection.

Regarding head machining, did you use same bit for second head? HSS works better on aluminum than carbide, preferably 2 flute. Wd40 makes an excellent cutting fluid to spray on while cutting.

[Michael Moore]

Yes, the same .5" HSS cutter with air blast to clear chips and lubricant went from "that was good, let's get the next one done" to "WTF?" straight away on the second head. RPM was set right and the feed and WOC/DOC were conservative. The head being annealed is the most likely culprit. When he gets a chance Jeff will try a test cut in some scrap 6061-T6 with the EM on his manual machine to confirm that it is still sharp.

[Norman]

Did these "powervalves" actually work? Does anybody knows more about them?

[husaberg]

Did these "powervalves" actually work? Does anybody knows more about them?

Looks like an atac valve.
They are just a chamber about the same size as the engines cylinder, and a butterfly valve.
They do work on increasing low end power as long as they are mounted close to the exhaust port.
They have been used in various incariations on Honda CR NS and MVX as well as the BSL500 and Cagivas.
http://i.ebayimg.com/00/s/NzY4WDEwMjQ=/z/BrAAAOSwT5tWNI~~/$_35.JPG

https://www.youtube.com/watch?v=zVY4PJP5WDg
Suzuki and Kawasaki have also used more compicated variations of exhaust chambers.

the this is how they work
note the butterfly is mounted 90' away from how it is pictured here
https://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=320342&d=1457837142https://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=307620&d=1420439122
This was Farmakens DIY effort (maybe not its a twin lol)
https://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=307606&d=1420439042https://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=307605&d=1420439042
https://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=307608&d=1420439042

[Flettner]

I think I might have seen those before :msn-wink:

How did they go in the end?

[husaberg]

I think I might have seen those before :msn-wink:
How did they go in the end?

not sure I just emailed KTM though they seem keen;)

Here is the farmaken
DIY verson he did a spool one as well
https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130357926#post1130357926
331020331021331022331023331024

[wobbly]

The ATAC idea is ideal for an MX type application, where extra power is needed well under the natural powerband the pipe is capable of.
In the two cases I have used this, the BSL and the 1090cc SeaDoo World Champ winning ski, it added nearly 30% power under the pipe.
But it is severely limited in that it only works up to a very set defined rpm, and then the valve must be shut instantly, or you then loose 30% above that rpm very quickly.
A PV working correctly is useful in shaping the powerband well under the pipe and right up to peak torque rpm as well.
Using both adds huge power everywhere if they are both digitally controlled correctly.

[husaberg]

The ATAC idea is ideal for an MX type application, where extra power is needed well under the natural powerband the pipe is capable of.
In the two cases I have used this, the BSL and the 1090cc SeaDoo World Champ winning ski, it added nearly 30% power under the pipe.
But it is severely limited in that it only works up to a very set defined rpm, and then the valve must be shut instantly, or you then loose 30% above that rpm very quickly.
A PV working correctly is useful in shaping the powerband well under the pipe and right up to peak torque rpm as well.
Using both adds huge power everywhere if they are both digitally controlled correctly.

Sounds like a job for a Solenoid like the Aprilia RS125 road bike had.

https://www.youtube.com/watch?v=owDt9MwfKI4
or if you are cheap almost all starter motors.

[chrisc]

Can someone with way more experience with high performance carbs please recommend me one. Freetech 50 engine, reed valve, with hopes to end up 16-18hp in the long run. Would like a TPS to run a 3D ignition map and wouldn't mind a powervalve to get the most out of it too.

[Norman]

Thank you for the replies regarding the ATAC/powervalve. I see there is no really good point in taking any short cuts if one wants to combine an ATAC function with a powervalve blade. The right way is to regulate through a solenoid with a distinct controlled on/off point.

Referring to welding, I asked a professional welder to test the Hobart MAXAL 4943, she usually TIG weld with 4043 (ALSi5). She liked the 4943 better, and it looked good. One of the good things with this material is that it is possible to heat treat to T6, after welding. I have not yet tried to heat treat, and machine it though. We did this try out welding on my RGV cylinder.

[Tim Ey]

I see there is no really good point in taking any short cuts if one wants to combine an ATAC function with a powervalve blade. The right way is to regulate through a solenoid with a distinct controlled on/off point.


Or one may combine it with the fullest opening of a Yamaha YPVS as presumably was done at Proton
331026
I can not imagine what the cigarette-box-alike attached to the YPVS will be otherwise.
Anyone got proof of my thoughts?

(I do not know how you guys deal with the copyright of pictures in this thread - This picture is from facebook. If it is not ok that i post it without a source let me know and I will delete it.)

[peewee]

Looks like KTM tried to do something more sophisticated like they told Neil Hints that they would. But eventually they found that the Kiwis already had a handle on it and KTM copied what was tried and true and already working properly in New Zealand.

long time ago I said there might be spies. figured someone would of snatched wobblys oval port cheetah idea and took it to market for themselves but I haven't seen any turn up.... yet :laugh:. just a matter of time I suppose

[seattle smitty]

Referring to welding, I asked a professional welder to test the Hobart MAXAL 4943, she usually TIG weld with 4043 (ALSi5). She liked the 4943 better, and it looked good. One of the good things with this material is that it is possible to heat treat to T6, after welding. I have not yet tried to heat treat, and machine it though. We did this try out welding on my RGV cylinder.


Last I checked, the big local welding supplier here was holding off of carrying the 4943 wire (which I was trying to buy), having had some negative feedback from the shipyards. If I can find out anything worthwhile, I'll pass it on.

[peewee]

FWIW, Jeff Henise and I spent the afternoon machining two TZ350 heads to convert them to replaceable combustion chamber inserts for his Bonneville LSR project.

I did a simple program at the mill and machined the first head and everything went along fine -- not as fast as possible (no flood coolant on my mill) but no excitement either.

The second head was a different story. It either at some point got hot enough in use to completely anneal it or that batch of heads was from a different alloy or HT spec from the first. Nasty gummy aluminum, building up on the cutter to the point of making the head extremely hot from rubbing as well as pushing it out of position (4 clamps, the first head had no problem) 2/3 of the way through the cycle.

It would be interesting to know what was going on. The same end mill that worked a treat on the first one immediately went into "I'm not happy" mode on the second one so we're pretty sure it was the head casting and not anything we were doing (same program as the first head). Slowing the feeds and RPM down by about 2/3 took some of the "why is the coolant smoking so much?" heat out of the head but even with that the EM was clearly pushing metal around instead of cutting it.

I guess it is just part of the mystique of old race bikes.

cheers,
Michael

just a shot in the dark here but when I do any heavy cutting with my carbides I run it in candle wax every so often and chews through alum like butter all day. without the wax it smears up the bit in minutes and its a bugger to clean out the teeth. if you cant run a continuos flow of cooling oil then maybe try drastically reduce the feed and bit speed

[peewee]

Looks like an atac valve.
They are just a chamber about the same size as the engines cylinder, and a butterfly valve.
They do work on increasing low end power as long as they are mounted close to the exhaust port.
They have been used in various incariations on Honda CR NS and MVX as well as the BSL500 and Cagivas.
http://i.ebayimg.com/00/s/NzY4WDEwMjQ=/z/BrAAAOSwT5tWNI~~/$_35.JPG

https://www.youtube.com/watch?v=zVY4PJP5WDg
Suzuki and Kawasaki have also used more compicated variations of exhaust chambers.

the this is how they work
note the butterfly is mounted 90' away from how it is pictured here
https://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=320342&d=1457837142https://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=307620&d=1420439122
This was Farmakens DIY effort (maybe not its a twin lol)
https://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=307606&d=1420439042https://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=307605&d=1420439042
https://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=307608&d=1420439042

I bet you forgot all about ktm's version

[jasonu]

just a shot in the dark here but when I do any heavy cutting with my carbides I run it in candle wax every so often and chews through alum like butter all day. without the wax it smears up the bit in minutes and its a bugger to clean out the teeth. if you cant run a continuos flow of cooling oil then maybe try drastically reduce the feed and bit speed

Stick fat like lard works great to keep cutters and abrasives clear but attracts pigeons and other wild life if you don't clean it up.

[2T Institute]

I think I might have seen those before :msn-wink:

How did they go in the end?

Never actually tested I have them at home now. The XR89 Suzuki RGV 500 uses a triple stage PV AND a AEC chamber. The AEC closes first then the PV opens. That was needed to pump up the bottom end to make the power linear.

[Michael Moore]

try drastically reduce the feed and bit speed

I did cut feed/RPM down midway through the second head which did help to reduce the heat in the part, but the metal was still very gummy. The original settings worked fine on the first head.

I've seen old machinists swear by the magic lubricating powers of bacon fat. It has to smell better than regular cutting fluid!

[husaberg]

Never actually tested I have them at home now. The XR89 Suzuki RGV 500 uses a triple stage PV AND a AEC chamber. The AEC closes first then the PV opens. That was needed to pump up the bottom end to make the power linear.

Cagiva combined a Atac with a PV as well, most of the need to do this i assume disappeared with the introduction of unleaded fuels.

[jonny quest]

Why would it disappear with the use of unleaded fuels?

[wobbly]

Most MX manufacturers have had a go at ATAC within the cylinder, or out the side or top.
Usually as the PV blade moves, it closes of a port to the chamber volume.
Fuel quality has no effect on the powerband width.

[guyhockley]

Thank you for the replies regarding the ATAC/powervalve. I see there is no really good point in taking any short cuts if one wants to combine an ATAC function with a powervalve blade. The right way is to regulate through a solenoid with a distinct controlled on/off point.
Not a very good picture, I'm afraid...

[Flettner]

long time ago I said there might be spies. figured someone would of snatched wobblys oval port cheetah idea and took it to market for themselves but I haven't seen any turn up.... yet :laugh:. just a matter of time I suppose
I guess so, the only plus is being able to say it was seen here on Kiwi Biker first. No, it was TSM first, whatever. I work by myself now, can you tell.
I have to admit this KTM's, YZ injection copy has got me fired up to finish the 360 reverse cylinder engine with the NEW injection layout. Link bless them are looking into supplying an ECU for this project, finally they can see I wan't full of shit after all, well not completely anyway.

[TZ350]

.

Injector Position

331035 331038

Central injector fires through a slot into the underside of the piston.

My favourite low speed injector position has been to fire under the piston. This seems to help enormously with fuel homogenization at lower and off pipe engine speeds.

331036

My least favorite and less successful position has been to inject directly across the crankcase into the oncoming inlet air stream. During periods of air flow reversion fuel gets blown out the inlet. And also at higher speed low throttle there is not enough time for a small squirt of fuel to travel right across the crankcase for even fuel distribution.

331037

Looking at a piston positioned slightly below transfer port opening the two clean spots at the edges look to me like marks left from air/fuel short circuiting from the A ports and washing the carbon away.

When I showed this to Flettner and asked about injector positioning. He suggested an injector in each of the A and B ports.

331033

Flettner suggested the B port injectors should handle the low speed fuel demand leaving only fresh air short circuiting from the A ports.

And any short circuiting is most likely at lower engine speeds before the reverse pressure wave action from the pipe blocks the exhaust port as the motor gets up into the power band.

At higher engine speeds when the motor is up on the pipe, then have the A port injectors chime in. That way with fuel injected into all four A and B ports the mixture should be pretty homogeneous. Flettner's idea sounds better than what I have been doing which is trying to combine two purely air streams from the A ports with two overly rich streams from the B ports and have them properly mix together in the cylinder.

As for problems coming back on the throttle after shutting off for a corner Nath88 suggested that at less than 20% throttle the EFI ECU needs to be able to differentiate between when the engine is firing and the pipe is sucking and creating a higher bulk air transfer through the motor and therefor fuel demand verses when the wave action in the pipe has totally collapsed and much less fuel is required.

The Alpha-N map can’t do this by itself, there needs to be some way for the ECU to tell if the engine is firing and the pipe sucking or not. Nath88 suggested measuring the return positive pressure pulse at the exhaust port. It is a great idea and I like it but unfortunately, I have not found a way to get my Ecotrons EFI software to do that.

Flettner suggested measuring the internal pipe pressure at the dwell section in the middle of the pipe. He pointed out that the pressure must drop when the wave action collapses and that by using a VE table below 20% throttle/load and Alpha-N above that I might be able to train the ECU to recognize when the motor is firing and wave action in the pipe is increasing demand for fuel.

I like Flettners idea of low speed injectors in the B ports and secondary injectors in the A ports that chime in when the fuel demand under full power/load requires all four injectors.

331034

I have ordered more parts from Ecotrons and my next challenge is a lack of room and to figure out how to fit a secondary injector close to the power valve actuator.

When I followed Nath88's very clever idea about using the return pressure wave at the exhaust port to see when the motor was firing. I ran into a problem, my ECU software averaged the low suction pulse and high plugging pulse and arrived at a lower average for on power open throttle compared to closed throttle. Makes sense when you think about it but I could not figure out how to get the ECU to make sense of it. Basically it needed to reduce fuel when the average pressure was higher and increase fuel when it was lower. This is opposite to the way EFI ECU's think.

In the mean time I am going to get this Beast going again and try Flettners idea and see what sort of average pressures are in the dwell mid section of the pipe and if the EFI ECU can make sense of them.

[Flettner]

Same, here you go KTM make This! The A port injection fueling will be super imposed over the normal fueling and largely run off information from the pipe pressure. At low speed no fuel to the A ports, just as our YZ is set up, at low speeds the gas energy exciting the ports is low, this is where short circuiting is worst . As the engine speed gets higher, pipe is working, the A port gas stream has some inertia, less short circuiting, that's when the A port injectors chime in. Should make for excellent harmonization when all injectors are firing. :bleh:

[husaberg]

Same, here you go KTM make This! The A port injection fueling will be super imposed over the normal fueling and largely run off information from the pipe pressure. At low speed no fuel to the A ports, just as our YZ is set up, at low speeds the gas energy exciting the ports is low, this is where short circuiting is worst . As the engine speed gets higher, pipe is working, the A port gas stream has some inertia, less short circuiting, that's when the A port injectors chime in. Should make for excellent harmonization when all injectors are firing. :bleh:

Doubling up the injectors therefore using 4 smaller individual injectors, will mean faster injector response which will buy you a lot more time. this should lessen the emissions as well as providing better fuel homogenisation.
Mazda rotaries responded really well to this approach, providing better power, plus far better drivablility in ported applications compared to the ubiquitous webber 48/51 IDA carb

[Norman]

Not a very good picture, I'm afraid...

Thank you very much for posting this article, have been looking for it at home from time to time, over the last 20 years or so, now I can finally put this to rest :-).

[Frits Overmars]

Same, here you go KTM make This! The A port injection fueling will be super imposed over the normal fueling and largely run off information from the pipe pressure. At low speed no fuel to the A ports, just as our YZ is set up, at low speeds the gas energy exciting the ports is low, this is where short circuiting is worst . As the engine speed gets higher, pipe is working, the A port gas stream has some inertia, less short circuiting, that's when the A port injectors chime in. Should make for excellent harmonization when all injectors are firing.So you decided to let the cat out of the bag. What we need now are injectors that are small enough and fast enough.

[TZ350]

What we need now are injectors that are small enough and fast enough.

I have personally run an Ecotrons small injector at 13,000 rpm in my 125cc two stroke engine ... http://www.ecotrons.com/components/fuel-injectors/

[Flettner]

So you decided to let the cat out of the bag. What we need now are injectors that are small enough and fast enough.
Yes Frits, I decided bugger it, there is nothing in it for anyway as I can't afford to go down the patent track. So if it's on here anyone can use it.

[Nath88]

.
When I followed Nath88's very clever idea about using the return pressure wave at the exhaust port to see when the motor was firing. I ran into a problem, my ECU software averaged the low suction pulse and high plugging pulse and arrived at a lower average for on power open throttle compared to closed throttle. Makes sense when you think about it but I could not figure out how to get the ECU to make sense of it. Basically it needed to reduce fuel when the average pressure was higher and increase fuel when it was lower. This is opposite to the way EFI ECU's think.


That's exactly the problem I'm having now... I've been experimenting with measuring the crankcase pressure instead of exhaust, just after transfers open. Under 25% throttle once on the pipe (7000 up) the pressure is lower than at 0% throttle... then over 25% the pressure starts going up. Which makes sense, the scavenge effect of the pipe drawing against the mostly closed throttle. But as you said, no good for a normal 4 stroke style ECU, it expects a linear input. I should put up some graphs of the data collected. Perhaps if you sampled the pressure before and after the transfers open then take the difference. The ability to write the code specifically for the engine is where KTM has a massive advantage.

At the moment I'm working on modifying the ECU code to capture the highest peak of the exhaust pulse as the port opens. I think this will be a good indicator of how much wave energy has gone into the pipe. So far the best results have been with the exhaust pressure at the powervalve vent. The PV housing was acting as a damper, smoothing the pressure pulse so the ECU could catch the peak easily, signal was a bit too smooth so I'm trying other methods, trying to nail an analog carb feel on throttle transitions. If the code mods don't work out (I'm no programmer), back up plan is to use a 'precision peak hold' circuit on the map sensor, then using the ignition output to reset the circuit at the start of each cycle. You could implement this on your ECU easily enough.

[husaberg]

Cagiva combined a Atac with a PV as well, most of the need to do this i assume disappeared with the introduction of unleaded fuels.


Why would it disappear with the use of unleaded fuels?
Sorry i missed your question, my take on it is.
When the Leaded (Jungle juice or rocket fuel )was banned and replaced with unleaded, the comp ratio were lowered and the 500's suddenly became a lot more user friendly to ride..
Of course at the same times big gains were made with ign mapping as well.
The power delivery was softened so much so, the NSR500 went back to the 180 two up two down crank not long after.
Doohan said they were not even real racing bikes after leaded was banned (or words to that effect)
The GP bikes were able to recoup the initial loss of HP rather quickly.
I am pretty sure the lower comp also allowed more over rev thus effectively widening the powerband, (But not 100% sure) if this was just a technological leap in jetting technology, or just becuse of the different burn characteritics of the lower comp and fuel.
Yamaha experimented with variable comp heads in the Rainey era due to the better effects on acceleration of high comp and better revabilty of low comp.
https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130892885#post1130892885
But in short i don't think the Comp ratio were ever raised again as high as they were in the leaded era.
Maybe Jan Frits or Wob will fill in the gaps or correct me.:wait:

[jamathi]

Sorry i missed your question, my take on it is.
When the Leaded (Jungle juice or rocket fuel )was banned and replaced with unleaded, the comp ratio were lowered and the 500's suddenly became a lot more user friendly to ride..
Of course at the same times big gains were made with ign mapping as well.
The power delivery was softened so much so, the NSR500 went back to the 180 two up two down crank not long after.
Doohan said they were not even real racing bikes after leaded was banned (or words to that effect)
The GP bikes were able to recoup the initial loss of HP rather quickly.
I am pretty sure the lower comp also allowed more over rev thus effectively widening the powerband, (But not 100% sure) if this was just a technological leap in jetting technology, or just becuse of the different burn characteritics of the lower comp and fuel.
Yamaha experimented with variable comp heads in the Rainey era due to the better effects on acceleration of high comp and better revabilty of low comp.
https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130892885#post1130892885
But in short i don't think the Comp ratio were ever raised again as high as they were in the leaded era.
Maybe Jan Frits or Wob will fill in the gaps or correct me.:wait:

At Aprilia we had more power, more over rev and no power loss at any part of the curve within 4 month's work, with a compression ratio of 1:16, without detonation. No changes to the cylinder were made, but some very serious research
to the cylinder head was very effective-- We were approaching 50HP at the time, 1998, no power jet....

[Frits Overmars]

At the moment I'm working on modifying the ECU code to capture the highest peak of the exhaust pulse as the port opens. I think this will be a good indicator of how much wave energy has gone into the pipe.Another option would be to look at the highest peak of the exhaust pulse after BDC, i.e. the return pulse. That will be an equally good indicator of how much wave energy has gone into the pipe, and it offers the additional advantage of knowing when this return pulse arrives back at the cylinder. If it's too early, lower the EGT by advancing the ignition timing; if it's too late, retard the ignition timing. That way you'll have a truly intelligent ignition and you can forget about EGT.


When the leaded was banned and replaced with unleaded, the comp ratios were lowered and the 500's suddenly became a lot more user friendly to ride... The GP bikes were able to recoup the initial loss of HP rather quickly.
I am pretty sure the lower comp also allowed more over rev thus effectively widening the powerband, (But not 100% sure) if this was just a technological leap in jetting technology, or just becuse of the different burn characteritics of the lower comp and fuel. But in short i don't think the Comp ratio were ever raised again as high as they were in the leaded era.
Maybe Jan Frits or Wob will fill in the gaps or correct me.What gaps Husa? You didn't leave much out.
A lower compression ratio forcibly yields a lower expansion ratio; less combustion energy is converted into torque by the time the exhaust opens and more of this energy remains in the exhaust gas in the form of higher pressure and higher temperature. This remaining energy drives the exhaust pulses, improving cylinder filling for the next combustion event, and the next, and the next.... This way a lower compression ratio can lead to higher power.
The lower comp ratio also made engines less sensitive to piston ring groove wear and ignition spark strength, and it helped overrev, so the bikes became easier to ride.
At the end of the lead-area the Aprilias had a compression ratio of 19,5. When lead was banned, this ratio was initially reduced to 14, after which it was gradually raised again. My personal preference would be to try even lower ratios in order to feed the pipe with even more energy.

[husaberg]

At Aprilia we had more power, more over rev and no power loss at any part of the curve within 4 month's work, with a compression ratio of 1:16, without detonation. No changes to the cylinder were made, but some very serious research
to the cylinder head was very effective-- We were approaching 50HP at the time, 1998, no power jet....




What gaps Husa? You didn't leave much out.
A lower compression ratio forcibly yields a lower expansion ratio; less combustion energy is converted into torque by the time the exhaust opens and more of this energy remains in the exhaust gas in the form of higher pressure and higher temperature. This remaining energy drives the exhaust pulses, improving cylinder filling for the next combustion event, and the next, and the next.... This way a lower compression ratio can lead to higher power.
The lower comp ratio also made engines less sensitive to piston ring groove wear and ignition spark strength, and it helped overrev, so the bikes became easier to ride.
At the end of the lead-area the Aprilias had a compression ratio of 19,5. When lead was banned, this ratio was initially reduced to 14, after which it was gradually raised again. My personal preference would be to try even lower ratios in order to feed the pipe with even more energy.

So knowing what you both know now, about how to get more power and disregarding the health and enviromental issues.
Would it still be unleaded or do you think you could get more power again with the leaded and appropriate mods?

[jamathi]

So knowing what you both know now, about how to get more power and disregarding the health and enviromental issues.
Would it still be unleaded or do you think you could get more power again with the leaded and appropriate mods?

I would stick with unleaded I think.
Of course many compression ratios were tried.
1:16 was the best on our dyno.
The teams had different choices, to adjust to the local atmospheric conditions.
And to avoid part-throttle detonation.
Health issues?
When we started using 'unleaded' we were given face masks....and gloves....

[Frits Overmars]

Unleaded, definitely.
The total energy content of a fuel is not dependent on its lead content. Plus, unleaded has a higher flame speed, reducing heat losses and NOx-formation.


Health issues? When we started using 'unleaded' we were given face masks....and gloves....Ah yes, the infamous Italian 'benzina verde' (green gasoline), the green probably refering to your face color after handling the stuff :sick:.


...disregarding the health and enviromental issues...You mean, like using Avgas? Low-Lead Aviation Gasoline, hah! I never figured out that first 'L'. The stuff contains five times as much lead as leaded car fuel.
They really should have used that L for Low energy content, because even regular pump petrol has a higher specific energy than avgas.
It's only benefit is that is counters detonation in unsound engines. I'd prefer to make those engines healthy instead of paying for poison.

[jamathi]

Unleaded, definitely.
The total energy content of a fuel is not dependent on its lead content. Plus, unleaded had a higher flame speed, reducing heat losses and NOx-forming.

A yes, the infamous Italian 'benzina verde' (green gasoline), the green probably hinting a your face color after handling the stuff :sick:.

It was all a stupid game started by Honda in 1982
Apparently they had no other means to raise power....at the time....

[husaberg]

It was all a stupid game started by Honda in 1982
Apparently they had no other means to raise power....at the time....

Pretty sure they introduced toulene into F1 about the same time.
i think their fuel was up to 90% at the peak of the turbo era. i can't recall what the rest was. something heptane i think
I think thats what they prop up modern unleaded fuel with even now (toulene)
To be fair though Shell and Yamaha (harris)were using uneaded about two years prior to the FIM changing the rules to ban leaded



You mean, like using Avgas? Low-Lead Aviation Gasoline, hah! I never figured out that first 'L'. The stuff contains five times as much lead as leaded car fuel.
They really should have used that L for Low energy content, because even regular pump petrol has a higher specific energy than avgas.
It's only benefit is that is counters detonation in unsound engines. I'd prefer to make those engines healthy instead of paying for poison.
while Avgas blue and green might have its issues it is at least very consistant between batches. not to mention available in the backwaters thanks to R22 Robinson Helicopters and dirty old Cessnas

[jamathi]

I think the first to use toluene in F1 was BMW.
The other teams discovered it by stealing a barrel of BMW's fuel....

[marsheng]

Another option would be to look at the highest peak of the exhaust pulse after BDC, i.e. the return pulse. That will be an equally good indicator of how much wave energy has gone into the pipe, and it offers the additional advantage of knowing when this return pulse arrives back at the cylinder. If it's too early, lower the EGT by advancing the ignition timing; if it's too late, retard the ignition timing. That way you'll have a truly intelligent ignition and you can forget about EGT.


That sounds like a excellent idea. Has it been tried before? Watching cht may be the way to control the mixture.

[bucketracer]

Thanks TeeZee, for a very simple approach to making oneself a reliable water cooled F4 Bucket engine with really good performance.

So simple, and no real tuning knowledge needed .....

https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1131032879#post1131032879

.... :2thumbsup (https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1131032879#post1131032879)

[husaberg]

I think the first to use toluene in F1 was BMW.
The other teams discovered it by stealing a barrel of BMW's fuel....

I have posted something about the toluene, but i doubt i could find it.
I know Yamaha audio taped the Big bang Honda and ran it through an oscilloscope to determine the crankshaft configuration.
Rather funny considering Honda first used their two up configuration the year before
According to Wayne Gardner Honda took previously hundreds of photos of an RGV500 from Wayne Gardner’s mirror glassed motorhome when someone was silly enough to leave on stripped down in front of it.
Gardner said that they blew them up to full scale and mocked up a bike and it was only then that they figured out that there path of moving the CG down was wrong.

Cagiva copied the RG500 suzuki about the same time as a set of works crankcases went missing from Suzuki GB, the YZR500 inline then the Yamaha V formations were also copied , it is said that they are so close that its possible to transfer internals, some say it was done with Yamaha approvial and consent.

[Frits Overmars]

Cagiva copied the RG500 suzuki about the same time as a set of works crankcases went missing from Suzuki GB, the YZR500 inline then the Yamaha V formations were also copied , it is said that they are so close that its possible to transfer internals, some say it was done with Yamaha approvial and consent.Both Honda and Yamaha were keen to keep Cagiva in the game for the sake of diversity. Cagiva had Wayne Rainey's championship-winning Yamaha YZR500 V-four on loan for a full month. I've still got the drawings of the Cagiva-cylinders somewhere; they were completely identical with the Yamaha-jugs. And Honda supplied Cagiva with not-for-sale Keihin carbs from their NSR500.

[philou]

Paton also received help from honda

Legend or truth?

[husaberg]

Honda supplied Cagiva with not-for-sale Keihin carbs from their NSR500.


Paton also received help from honda
Legend or truth?
They (Honda) from what i heard also supplied those carbs to Patton. Although i think that was maybe Burgess himself, who felt sorry for them when he heard honda quoted them over 100K for a set.


Both Honda and Yamaha were keen to keep Cagiva in the game for the sake of diversity. Cagiva had Wayne Rainey's championship-winning Yamaha YZR500 V-four on loan for a full month. I've still got the drawings of the Cagiva-cylinders somewhere; they were completely identical with the Yamaha-jugs. .



I cetainly wouldn't mind seeing those drawings
There is a line drawing for most of the up to mid nineties engine at one of the japanese museums, i have tried to get a decent pic of it but no luck yet.
331070 background of pic..........

[jamathi]

For the 500/4 Honda had an instruction book for mechanics.
It was made in such a way that it could not be foto copied...

[jamathi]

After John Kocinsky won the 250 championship on Yamaha his bike was given to Gilera.
Gilera had very little success with the bike they made after that.
They had a totally unable boss, a certain Mr Martini.
Many millions were spent without any result....
Several top riders were engaged, and paid a lot, but they never even won 1 race.
They also engaged Bartol, but the results didn't come....
Total failure, like never seen before, or since.

Some years later, Aprilia boss Giampiero Sacchi had an Aprilia painted in Gilera colours.
And Marco Simoncelli won the world championship on it.....
Funny things happen sometimes!

[jamathi]

One of the Derbi mechanics, an Italian, had a big garage under his house.
He rented this out to a Honda team.
Of course he had access to his own garage.
And he took a Honda works cylinder to DERBI for me to look at.....
But the DERBI cylinder was already a copy from Honda, made by Bartol.
Copied by him in more or less the same way, also for Yamaha.
When he went from DERBI to KTM he stole all the fairing models, made by Porsche and paid for by DERBI.

[husaberg]

After John Kocinsky won the 250 championship on Yamaha his bike was given to Gilera.
Gilera had very little success with the bike they made after that.
They had a totally unable boss, a certain Mr Martini.
Many millions were spent without any result....
Several top riders were engaged, and paid a lot, but they never even won 1 race.
They also engaged Bartol, but the results didn't come....
Total failure, like never seen before, or since.

Some years later, Aprilia boss Giampiero Sacchi had an Aprilia painted in Gilera colours.
And Marco Simoncelli won the world championship on it.....
Funny things happen sometimes!

Gilera VS Aprilia
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839&attachmentid=301353
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839&attachmentid=301352
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839&attachmentid=301351
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839&attachmentid=301350
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839&attachmentid=301349
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839&attachmentid=301348
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839&attachmentid=301347

[Haufen]

One of the Derbi mechanics, an Italian, had a big garage under his house.
He rented this out to a Honda team.
Of course he had access to his own garage.
And he took a Honda works cylinder to DERBI for me to look at.....
But the DERBI cylinder was already a copy from Honda, made by Bartol.
Copied by him in more or less the same way, also for Yamaha.
When he went from DERBI to KTM he stole all the fairing models, made by Porsche and paid for by DERBI.

Do you think it was the other way round, too? In that Honda knew what the Aprilia cylinders looked like and had measurements taken or even tested them?

[jamathi]

Do you think it was the other way round, too? In that Honda knew what the Aprilia cylinders looked like and had measurements taken or even tested them?

Yes, I think so.
Aprilia once supplied REPSOL with an engine for fuel testing......never came back....
And then there are always the mechanics trying to make some extra money!
Honda started their 250 project by buying and testing a Rotax 250 tandem.
Just as they started making racing bikes after Mr Honda was presented with a Mondial works bike.
Copying does not matter too much as long as you keep having new ideas....

[breezy]

331087
Jan, Frits,
do we have a graph showing exhaust valve position to run along side this attachment... or did it not change at all until a certain level of rpm was achieved?( im sure this has been spoken about before but im struggling to find...). also how much exhaust duration was there prior to it being activated? thanks:sherlock:

[jamathi]

331087
Jan, Frits,
do we have a graph showing exhaust valve position to run along side this attachment... or did it not change at all until a certain level of rpm was achieved?( im sure this has been spoken about before but im struggling to find...). also how much exhaust duration was there prior to it being activated? thanks:sherlock:

This was never done I think....
And I don't remember the answer to your second question, might have been around 170°.

[Frits Overmars]

Both Honda and Yamaha were keen to keep Cagiva in the game for the sake of diversity. Cagiva had Wayne Rainey's championship-winning Yamaha YZR500 V-four on loan for a full month. I've still got the drawings of the Cagiva-cylinders somewhere; they were completely identical with the Yamaha-jugs. And Honda supplied Cagiva with not-for-sale Keihin carbs from their NSR500.

I cetainly wouldn't mind seeing those drawings.Alas, once again me and my archives are not in the same country. But you don't miss much, Husa. Yamaha's biggest step in the latter days of their two-stroke activities was to copy Honda cylinders :bleh:.


For the 500/4 Honda had an instruction book for mechanics. It was made in such a way that it could not be foto copied.......But somehow a copy of that instruction book found its way to my archive anyway. And that is a very instructive document. But as I'm not supposed to have it,
I hesitate to put it on an open forum. And no, I won't respond to PM-requests in this case. It's a big pile of paper anyway and I don't have a scanner.


do we have a graph showing exhaust valve position to run along side this attachment... or did it not change at all until a certain level of rpm was achieved?( im sure this has been spoken about before but im struggling to find...). also how much exhaust duration was there prior to it being activated?We don't, Breezy; not a graph. I should be able to draw one because I must have a table of rpm/valve positions somewhere, but not within reach.
The closed-valve exhaust timing was 172°.

[TZ350]

Got a new computer and thanks to Neels help I managed to easily install the latest version of EngMod2T on it. Great help from Neels.

Used EngMod2T to develop a PoweValve curve for my new NSR/GP110 cylinder.

I thought that a PV curve would be a straight line steadily increasing as the revs go up, but it looks like that is not necessarily so.

331088

I have a list of the break points for the PV curve developed from the EngMod simulations. And now I need to find the corresponding mV feedback breakpoints for the servo motor that drives the PV.

331089

Using a degree wheel and the list of breakpoints for the PV.

331091

I developed the PV mV control curve by adjusting the servo feedback required to match the PV blade to the degrees ATDC to Exhaust/Power Valve opening position at each point on the curve.

331090

Half an hour later and I have a new PV curve setup in the Ignitec ignition module.

Basically there are three steps, 8-10k, 10-11k, and 11-12.5k. the hump at the end is just to move the PV completely out of the way in the extreme over rev region.

The next stop, the dyno.

[Frits Overmars]

Nice injector position TeeZee :D.

331093
Oops. I stored the above picture as 'TZ350 cylinder'. But now I must forever remember that it is not a Yamaha TZ350-cylinder :confused:.

[husaberg]

Alas, once again me and my archives are not in the same country. But you don't miss much, Husa. Yamaha's biggest step in the latter days of their two-stroke activities was to copy Honda cylinders :bleh:.

....But somehow a copy of that instruction book found its way to my archive anyway. And that is a very instructive document. But as I'm not supposed to have it,
I hesitate to put it on an open forum. And no, I won't respond to PM-requests in this case. It's a big pile of paper anyway and I don't have a scanner.
.

You really need to set up a portable expansion drive or start backing up to Cloud.
Funny enough the Suzuki that KR JR rode to victory had exhausts that were copies of a Yamaha YZR they never gave any more power on the dyno but they lapped a second or two faster with them on.
Willings spilled that one. pretty sure the rest was out of the Yamaha play book as well. So that might have been also a Honda by default.
I noticed that the later 90's RGV500 had a spool PV as well as a blade anyone got pics of that?

PS you tease you know i am a NSR anorak , i also have a have a scanner and contary to popular opinion i are actually very discrete, you really should see the stuff i don't post on the web.:whistle:
MY japanese contact was meant to take some decent photos of the line drawing for the YZR's but i think he has forgotten.
I do have a scale line drawing for the chassis of the later ones.

[philou]

Yamaha's biggest step in the latter days of their two-stroke activities was to copy Honda cylinders :bleh:.



http://img4.hostingpics.net/pics/544431IMG0268.jpg

http://img4.hostingpics.net/pics/128401IMG0265.jpg

http://img4.hostingpics.net/pics/967969IMG0264.jpg

http://img4.hostingpics.net/pics/569084IMG0256.jpg

[Frits Overmars]

I noticed that the later 90's RGV500 had a spool PV as well as a bladeWasn't it two or three blades for the exhaust powervalve and a spool valve for the exhaust resonance chamber?


You really need to set up a portable expansion drive or start backing up to Cloud.Can you teach me how to put tons of paper in this cloud? It's not like I have a spare year available for scanning the lot before uploading it, even if I had a scanner.

Anyway:
331098

[breezy]

This was never done I think....
And I don't remember the answer to your second question, might have been around 170°.

ok thanks for reply.

[breezy]

Alas, once again me and my archives are not in the same country. But you don't miss much, Husa. Yamaha's biggest step in the latter days of their two-stroke activities was to copy Honda cylinders :bleh:.

....But somehow a copy of that instruction book found its way to my archive anyway. And that is a very instructive document. But as I'm not supposed to have it,
I hesitate to put it on an open forum. And no, I won't respond to PM-requests in this case. It's a big pile of paper anyway and I don't have a scanner.

We don't, Breezy; not a graph. I should be able to draw one because I must have a table of rpm/valve positions somewhere, but not within reach.
The closed-valve exhaust timing was 172°.

ok, thanks for reply.

[husaberg]

Wasn't it two or three blades for the exhaust powervalve and a spool valve for the exhaust resonance chamber?

Can you teach me how to put tons of paper in this cloud? It's not like I have a spare year available for scanning the lot before uploading it, even if I had a scanner.

Anyway:
331098
You might be right re the RGV
331099
As for your paper documents, I would be glad to teach you how
All you need to do is mail them to husaberg scanning and uploading services Wild Wild West NZ

[1948rod]

You might be right re the RGV
331099
As for your paper documents, I would be glad to teach you how
All you need to do is mail them to husaberg scanning and uploading services Wild Wild West NZ

Hi I have a reverse cylinder tz250 in pieces. It has spare y1 and y2 cylinders. Can these cylinders be bored out to fit Tz 350 Pistons to put onto a kart for hill climbing. Are the Tz cylinders Able to be fitted to a spare Rgv bottom end. Would these cylinders be much better than bored out rgv barrels.

[Flettner]

Husaberg, your the search engine of choice, can you find the KTM patent on this new TPI system? Keep digging until you get traction.
Mostly interested in the date it was filed.

[Grumph]

Husaberg, your the search engine of choice, can you find the KTM patent on this new TPI system? Keep digging until you get traction.
Mostly interested in the date it was filed.

Opposing it on "prior art" grounds ?

Best case outcome would be a payoff from KTM - which wouldn't be bad surely ?

[F5 Dave]

Far more important; bragging rights.

[TZ350]

Nice injector position TeeZee :D.

331093

Yes, a lot of us have copied Flettners original idea he posted ages ago, even KTM have done it......... :laugh:

[TZ350]

... a reliable water cooled F4 Bucket engine with really good performance.

So simple, and no real tuning knowledge needed .....

https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1131032879#post1131032879

.... :2thumbsup (https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1131032879#post1131032879)

In "Bucket terms" it is pretty simple to bolt a NSR cylinder onto a Suzuki GP100 bottom end.

[TZ350]

Page 1740 ........

Links to a whole bunch of EFI projects.

EFI Kawasaki Bighorn on the dyno https://youtu.be/ifSEql1X4R0
EFI Kawasaki Bighorn Trail ride 1 https://youtu.be/eleqBGvOM4M
EFI Kawasaki Bighorn Trail Ride 2 https://youtu.be/CnIemdISKrM
EFI Kawasaki Bighorn VMX https://youtu.be/v8i6ps0PdVI

Maramarua classic forest trail ride https://youtu.be/ZqzOgOJuJ1E

EFI YZ dyno run https://youtu.be/UEQli7nuak4
EFI YZ250 look around and first start up https://youtu.be/hOGZ5llowoU
EFI YZ250 trail ride 1 https://youtu.be/1YG9ko8-Nwk

Nath88?
EFI first start up https://youtu.be/wIRF3VJUqBk
EFI ride around the block https://youtu.be/4Zsz26QmfAU

CVT EFI NOS and everything else https://youtu.be/A9d-atuQO7Y
EFI and Turbo Snow Cat https://youtu.be/U1uz7gdS-cA
SeeDoo Etec https://youtu.be/LhNHcy9si5o

1975 Suzuki GT250 road bike fuel injected start up https://youtu.be/A7fONUsJQD4
1975 Suzuki GT250 road bike fuel injected road test https://youtu.be/BePHcg5dNjw

Fuel injected 1971 Yamaha R5 https://youtu.be/qzVHgHJ9PWI

Athena Direct Injection https://youtu.be/h-F_IndOm5I

BRC 250 EFI kart engine https://youtu.be/dNat9ZwWbq8
BRC 250 EFI kart engine https://youtu.be/Kfx61bUOznc

Racing EFI Vespa https://youtu.be/_sjx2i4xFlY

EFI Banshee first start https://youtu.be/e1WHVVT6d9c
EFI Banshee run https://youtu.be/eznxX_ndpII

Direct injection https://youtu.be/IpjWi-0qTJg

Will direct injection DI save two strokes https://youtu.be/ql2-wW0LuWY

Orbital direct injection https://youtu.be/fIoB0zTeUAY

EFI Dragbike Thailand https://youtu.be/VB6Q_fQQ_PY

Mega Squirt YZ125 https://youtu.be/Di8FuHApLKA

Aprilia RSi 125 EFI Part 1 https://youtu.be/S1xvr_VXzx4
Aprilia RSi 125 EFI Part 2 https://youtu.be/j5FOUn7V3nc
Aprilia RSi 125 EFI Part 3 https://youtu.be/WBaiMJb6ntY
Aprilia RSi 125 EFI Part 4 https://youtu.be/pZl5KPwvm0s

EFI 125 kart engine https://youtu.be/4D8WRjDxan0
EFI 125 kart engine https://youtu.be/b1YbPdw00Ww
EFI 125 kart engine https://youtu.be/r5ljaDdaH_o
EFI 125 kart engine https://youtu.be/uexMJbtyZdU
EFI 125 kart engine https://youtu.be/uzbSsYh8Z9w
EFI 125 kart engine https://youtu.be/XIcX9-GsMGQ
Fuel injected Kart https://youtu.be/R5_KlcefQ8k

2017 KTM dyno https://youtu.be/8g0uSIisMtI
2017 KTM demo ride https://youtu.be/nf1tfdUtjJI

EFI CR250 https://youtu.be/VlHyRcmlLgU http://www.supermototecnica.<wbr>com/2015/09/10/sviluppi-del-<wbr>sistema-iniezione-diretta-<wbr>indiretta-due-tempi/ (http://www.supermototecnica.com/2015/09/10/sviluppi-del-sistema-iniezione-diretta-indiretta-due-tempi/)

EFI YZR500 https://youtu.be/tNAtmKzqo9A

EFI CR500 https://youtu.be/BskSxMoQrwA

2T Nitro Engine visible combustion https://youtu.be/aO5Qkzlo2Kw
2T visible combustion https://youtu.be/G7PSec7RjRw
More 2T Visible combustion https://youtu.be/BrWpF6YiSDs

Fuel Burn in a side valve 4T https://youtu.be/jdW1t8r8qYc
4T Visible fuel burn https://youtu.be/31mtOdHGbB4

[jasonu]

Far more important; bragging rights.

and some fat $stacks$ too.....

[SwePatrick]

https://scontent.xx.fbcdn.net/v/t31.0-8/18673161_10154971273409475_8188424143011949589_o.j pg?oh=77baa336cfa43d71055cb0d85e51612b&oe=59B3D1CB
https://scontent.xx.fbcdn.net/v/t1.0-9/18671021_10154972195909475_7232125025488378224_n.j pg?oh=5150f899fa62e252b28e38362a775d54&oe=59E42B20

A little more progress.
1st race in ~3 weeks.
Are tuning the engine as we speak.
And 211.2cc on methanol sounds angry at 13000rpm ;)
Will post a video later on when i got it fully tuned.

[Flettner]

Opposing it on "prior art" grounds ?

Best case outcome would be a payoff from KTM - which wouldn't be bad surely ?

Nah, not interested in a payout (it would never happen anyway) I just think it would be a bit rich if KTM have patented my idea and legally leaned on me when I start production of my own injected engines.
The idea behind showing it off on the internet was so the technology is available for anyone to use if they so wanted. Couldn't be patented , prior knowledge according to my patent attorney.
He said they are probably bluffing.
Yes Dave, I could live with bragging rights:drinkup::drinkup:

[SwePatrick]

That's exactly the problem I'm having now... I've been experimenting with measuring the crankcase pressure instead of exhaust, just after transfers open. Under 25% throttle once on the pipe (7000 up) the pressure is lower than at 0% throttle... then over 25% the pressure starts going up. Which makes sense, the scavenge effect of the pipe drawing against the mostly closed throttle. But as you said, no good for a normal 4 stroke style ECU, it expects a linear input. I should put up some graphs of the data collected. Perhaps if you sampled the pressure before and after the transfers open then take the difference. The ability to write the code specifically for the engine is where KTM has a massive advantage.

At the moment I'm working on modifying the ECU code to capture the highest peak of the exhaust pulse as the port opens. I think this will be a good indicator of how much wave energy has gone into the pipe. So far the best results have been with the exhaust pressure at the powervalve vent. The PV housing was acting as a damper, smoothing the pressure pulse so the ECU could catch the peak easily, signal was a bit too smooth so I'm trying other methods, trying to nail an analog carb feel on throttle transitions. If the code mods don't work out (I'm no programmer), back up plan is to use a 'precision peak hold' circuit on the map sensor, then using the ignition output to reset the circuit at the start of each cycle. You could implement this on your ECU easily enough.


I often use pipe pressure as a measuringtool when tuning twostrokes.
I weld a bung on the middle of the 'Belly' on the pipe.
Then connect the pipe through the bung to a simple turbopressure gauge.
To even out the pulses a bit i use a simple fuelfilter in-line on the hose.
I also use a restrictor before the filter, between pipe and filter just to get the pulses less intense.

Maybe it works the same way, but instead of a pressuregauge, you can put a mapsensor, 0-5v.

(And as we speak i use an adjustable 'restrictor' as the bung has two functions now.
When not measuring pressure i use the bung to pressurise the fueltank, with this restrictor i can adjust fuelpressure.)

331117

[ief]

This guy claims it's not a KTM patent at all (?)

https://www.youtube.com/watch?v=f1TVszsAXc8

[husaberg]

Hi I have a reverse cylinder tz250 in pieces. It has spare y1 and y2 cylinders. Can these cylinders be bored out to fit Tz 350 Pistons to put onto a kart for hill climbing.
No idea but unlikely, Hans Hummel made a 350 cylinder conversion kit for the V twin though.

Are the Tz cylinders Able to be fitted to a spare Rgv bottom end.
Anythings possible given enough time and money

Would these cylinders be much better than bored out rgv barrels.
No need to bore out RGV cylinders use either Arctic Cat ZRT600 2001 cylinders or RG200 they both bolt on to RGV's
As do RG150 wolf.

There was a guy who made up a close to 400cc 1kt TZR using DT200 cylinders and a stroked crank, But WR200 cylinders would have been better.

[husaberg]

Husaberg, your the search engine of choice, can you find the KTM patent on this new TPI system? Keep digging until you get traction.
Mostly interested in the date it was filed.

I couldn't find it the other day they don't list patent numbers which suggests to me they either don't have international pattents yet or they are pending.
Either that or they are not in their own name.
I find it hard to believe Boyseen never pattented it, they pattented just about everything else.

[jonny quest]

Let me know if going after KTM works Flettner. That would give me motivation to go after Suzuki with their VVT on the GSXR 1000.

[jonny quest]

Apparently there will be no tuning software available from KTM for the new FI 2 stroke offroad models.

That's going to complicate things.....

[Tim Ey]

Apparently there will be no tuning software available from KTM for the new FI 2 stroke offroad models.

That's going to complicate things.....

Even for offical KTM Dealers this has been standard (on foulstroke): You may choose between standard mappings for different countrys and Akrapovic mapping with / wo catalysator.
Nothing more . :confused:

[jonny quest]

Even for offical KTM Dealers this has been standard (on foulstroke): You may choose between standard mappings for different countrys and Akrapovic mapping with / wo catalysator.
Nothing more . :confused:

KTM used to offer a tuning kit for sale for the 4 strokes. Available to the public. They don't offer that anymore. Harley Davidson was fined by the EPA for selling/allowing customers to modify EPA regulated settings. KTM has decided they didn't want to be liable. So no software will be able from now on.

Hopefully hackers will step in

[Brett S]

Here's an old Rotax patent from 2004 with twin conventional injectors in transfer ports but aiming into cylinder area: CLICK HER (https://worldwide.espacenet.com/publicationDetails/biblio?CC=US&NR=6691649B2&KC=B2&FT=D&ND=&date=20040217&DB=&locale=#)E

Latest one from rotax 2016 combining DFI with indirect FI (IFI?) and it's control system: CLICK HERE (https://worldwide.espacenet.com/publicationDetails/biblio?CC=WO&NR=2016193902A2&KC=A2&FT=D&ND=&date=20161208&DB=&locale=#)

BEtaMotor has gone a different way in 2017 with IFI? almost throttle body injection: CLICK HERE (https://worldwide.espacenet.com/publicationDetails/biblio?DB=EPODOC&II=0&ND=3&adjacent=true&locale=en_EP&FT=D&date=20170111&CC=EP&NR=3114334A1&KC=A1#):

The biggest hurdle to playing with these KTM's will be getting someone to reverse engineer the KTM ecu's algorithm's and map locations and more importantly share it.
If KTM allowed the world to tinker with it the improvements would come much quicker. Unfortunately this won't happen.

[41juergen]

To all who have more experience with EngMod than I have:
are the shown temps reasonable for a setup with a cooling water temp of approx. 50°C in the head (like in the RSA125)?
331137

[wobbly]

Here is the file that gives good dyno correlation for the RSW.

[Flettner]

[QUOTE=Brett S;1131048534]Here's an old Rotax patent from 2004 with twin conventional injectors in CC=US&NR=6691649B2&KC=B2&FT=D&ND=&date=20040217&DB=&locale=#"]CLICK HER[/URL]E
/QUOTE]

That looks like their second development cylinder attempt, the first 'click here'

[TZ350]

My original post has a lot of links to interesting 2T EFI projects like this one:- EFI CR250 https://youtu.be/VlHyRcmlLgU

http://www.supermototecnica.<wbr>com/2015/09/10/sviluppi-del-<wbr>sistema-iniezione-diretta-<wbr>indiretta-due-tempi/ (http://www.supermototecnica.com/2015/09/10/sviluppi-del-sistema-iniezione-diretta-indiretta-due-tempi/)


Fuel Burn in a side valve 4T https://youtu.be/jdW1t8r8qYc

4T Visible fuel burn https://youtu.be/31mtOdHGbB4

This guy has posted on YouTube a whole lot of slow motion videos of a B&S engine with a clear plastic head burning different fuels. Very interesting that petrol showed the sort of visible combustion flame you would expect and Acetone showed no flame color at all.

[41juergen]

Here is the file that gives good dyno correlation for the RSW.
Perfect, thank's Wob...

[jamathi]

We used a dyno room temperature of 27°C at Aprilia.
It 'cost' us some power.....about 1,5.
But it was the average temperature of the various circuits we raced on!
It also was very comfortable in the winter....

[41juergen]

We used a dyno room temperature of 27°C at Aprilia.
It 'cost' us some power.....
But it was the average temperature of the various circuits we raced on!

Jan, the engine took the air out of the cell, right? So no specific "single" air handling system supplying only "intake air"?

[husaberg]

Husaberg, your the search engine of choice, can you find the KTM patent on this new TPI system? Keep digging until you get traction.
Mostly interested in the date it was filed.

Not Ktm but interesting
http://papers.sae.org/2012-32-0115/

I think this predates the Flettner TPI.
https://www.google.com/patents/US6691649

KTMs patents might be related to the electronic oil injection.
Whicjh i believe are held by the Mikuni or Keihin

[guyhockley]

https://www.kiwibiker.co.nz/forums/images/BP-Brown/misc/quote_icon.png Originally Posted by 1948rod https://www.kiwibiker.co.nz/forums/images/BP-Brown/buttons/viewpost-right.png (https://www.kiwibiker.co.nz/forums/showthread.php?p=1131048360#post1131048360)

Hi I have a reverse cylinder tz250 in pieces. It has spare y1 and y2 cylinders. Can these cylinders be bored out to fit Tz 350 Pistons to put onto a kart for hill climbing.

No idea but unlikely, Hans Hummel made a 350 cylinder conversion kit for the V twin though. https://www.kiwibiker.co.nz/forums/images/BP-Brown/misc/quote_icon.png Originally Posted by 1948rod https://www.kiwibiker.co.nz/forums/images/BP-Brown/buttons/viewpost-right.png (https://www.kiwibiker.co.nz/forums/showthread.php?p=1131048360#post1131048360)

Are the Tz cylinders Able to be fitted to a spare Rgv bottom end.




Anythings possible given enough time and money
https://www.kiwibiker.co.nz/forums/images/BP-Brown/misc/quote_icon.png Originally Posted by 1948rod https://www.kiwibiker.co.nz/forums/images/BP-Brown/buttons/viewpost-right.png (https://www.kiwibiker.co.nz/forums/showthread.php?p=1131048360#post1131048360)
Would these cylinders be much better than bored out rgv barrels.



No need to bore out RGV cylinders use either Arctic Cat ZRT600 2001 cylinders or RG200 they both bolt on to RGV's
As do RG150 wolf.

If this article is typical, the Hans Hummel conversion is slightly bigger than 350, might require a lot of engineering just to fit in a 350 class? A bloke who was trying very hard to sell me some HH350 barrels claimed they used standard KTM 250 pistons. Those ones were for a reverse cylinder TZ, no idea about interchangeability with other Yams.
There was also a Roll TZ360 conversion, try searching on
http://www.igkoenigsklasse.de
There used to be siegertyamaha.com that sold stuff like that but the website seems to have died.

Closer to (my) home, the F350 sidecar class now seems to be flooded with Banshee motors, but, previously, there were Yam V-twin 350s and at least one competitor (John Crick?) had a 350 RGV. Some, or all, of these may have come from George Hardwick (GHR) who has unfortunately now died and his website is gone as well.
NB. I've no involvement or experience with F350 so the above is just based on reading reports in BSN, perhaps Mr Jones may correct me if I've misremembered.

A couple of UK tuners did 300 big bores for RGV/RS250 engines, at one point, Wiseco UK listed the 60mm piston in their catalogue.
I looked at RGVs for a project and seem to remember they have a very wide ratio gearbox or maybe just a really low 1st?

[jamathi]

Jan, the engine took the air out of the cell, right? So no specific "single" air handling system supplying only "intake air"?

We had an air conditioned dyno room where we could use the temperature and humidity we wanted.
The results were corrected for atmospheric pressure.
Our measurements were very precise and repeatable.
Air 'quality' was another matter.
I had the oxygen content measured, it varied from 19-21% in a week.
This explained some 'unexplainable' differences from day to day.

[husaberg]

If this article is typical, the Hans Hummel conversion is slightly bigger than 350, might require a lot of engineering just to fit in a 350 class? A bloke who was trying very hard to sell me some HH350 barrels claimed they used standard KTM 250 pistons. Those ones were for a reverse cylinder TZ, no idea about interchangeability with other Yams.
There was also a Roll TZ360 conversion, try searching on
http://www.igkoenigsklasse.de
There used to be siegertyamaha.com that sold stuff like that but the website seems to have died.

Closer to (my) home, the F350 sidecar class now seems to be flooded with Banshee motors, but, previously, there were Yam V-twin 350s and at least one competitor (John Crick?) had a 350 RGV. Some, or all, of these may have come from George Hardwick (GHR) who has unfortunately now died and his website is gone as well.
NB. I've no involvement or experience with F350 so the above is just based on reading reports in BSN, perhaps Mr Jones may correct me if I've misremembered.

A couple of UK tuners did 300 big bores for RGV/RS250 engines, at one point, Wiseco UK listed the 60mm piston in their catalogue.
I looked at RGVs for a project and seem to remember they have a very wide ratio gearbox or maybe just a really low 1st?

Pretty sure there was a few versions with different capascities there was a 54mm stroke and a 50.6mm one.
I think they were originally made for a German (whose name escapes me) that ran one in the 500GP class. this was before the Aprilia "super bored 250" effort.
It used to stand out as it seemed to be doing half the revs of the rest of the feild.
It could beat a RS500 honda which were still running about at the rear of the feild until the Harris and ROC yamahas became available.
They had to be bigger than 350cc as a result of the old rule to prevent the likes of tz350's running with the big boys.
The rule was never altered when the 350 class was dropped.

people here run the nsr300's that have NSR150 cylinders on NSR250's.
At least one i understand is working on a long stroke crank to get it close to the F3 limit. of 400cc for a road based 2t.
Most of the RGV300s are simply made out of the RG150 cylinders.
if you want to add a earlier RG250 crank 54mm stroke you could make up a pretty decent engine but i don't think the gearbox is that reliable.
you can get dry clutch and close ratio gears for the rgv but the RS honda stuff and the F3 stuff for relevent years is far more common and fits, as does the TZ stuff in the TZR v twins.
TZR V twins twins were never that common here not sure why. Yet we brought in shit loads of Japanese imports (grey in the UK) but most were NSR or RGV.

[koenich]

Which i believe are held by the Mikuni or Keihin
In one video (can't recall which though) it was mentioned that it might be a Mikuni patent and that is also the reason they switched to Mikuni carbs for the '17 models.

[Peter1962]

In one video (can't recall which though) it was mentioned that it might be a Mikuni patent and that is also the reason they switched to Mikuni carbs for the '17 models.

I do not understand how any firm could obtain a patent, for a technique where there are clearly examples of people who experiment with variations on the same theme since years...
Is this bluff poker from KTM ?

[Moooools]

I do not understand how any firm could obtain a patent, for a technique where there are clearly examples of people who experiment with variations on the same theme since years...
Is this bluff poker from KTM ?

1. The patent could be quite old.
2. The patent application could have left out prior art knowingly, and accepted that the patent may be invalidated should someone with deep enough pockets try.
3. The patent could be much narrower than simply 'transfer port injection'. It could, for instance, include independent claims surrounding injector spray patterns, ECU control methods etc.
4. Some other reason not obvious to us. Patents are complex to deal with, hence the need for patent attorneys.

[guyhockley]

Pretty sure there was a few versions with different capascities there was a 54mm stroke and a 50.6mm one.
I think they were originally made for a German (whose name escapes me) that ran one in the 500GP class. this was before the Aprilia "super bored 250" effort.
It used to stand out as it seemed to be doing half the revs of the rest of the feild.
It could beat a RS500 honda which were still running about at the rear of the feild until the Harris and ROC yamahas became available.
They had to be bigger than 350cc as a result of the old rule to prevent the likes of tz350's running with the big boys.
The rule was never altered when the 350 class was dropped.

people here run the nsr300's that have NSR150 cylinders on NSR250's.
At least one i understand is working on a long stroke crank to get it close to the F3 limit. of 400cc for a road based 2t.
Most of the RGV300s are simply made out of the RG150 cylinders.
if you want to add a earlier RG250 crank 54mm stroke you could make up a pretty decent engine but i don't think the gearbox is that reliable.
you can get dry clutch and close ratio gears for the rgv but the RS honda stuff and the F3 stuff for relevent years is far more common and fits, as does the TZ stuff in the TZR v twins.
TZR V twins twins were never that common here not sure why. Yet we brought in shit loads of Japanese imports (grey in the UK) but most were NSR or RGV.

RG crank centre is quite different to the RGV, is it easily interchangeable?
Here's a Hummel 375 with a 54mm crank:
http://www.geckomotorcycles.co.uk/magento/4dp-3xv-yamaha-tz-375cc-hh-big-bore-kit.html

[guyhockley]

Just found that I'd saved this from the GHR website. He had a 500 triple, too but don't seem to have anything on that.

[monkeyfumi]

Most of the RGV300s are simply made out of the RG150 cylinders.


No, they are just bored out and replated standard cylinders (with all the compromises that brings)

[guyhockley]

http://img4.hostingpics.net/pics/544431IMG0268.jpg

http://img4.hostingpics.net/pics/128401IMG0265.jpg

http://img4.hostingpics.net/pics/967969IMG0264.jpg

http://img4.hostingpics.net/pics/569084IMG0256.jpg


Cagiva cylinder from 1988-89:

[Tim Ey]

I have a question: Does an owner of a Honda NSR250 cylinder or head may print this out
331151
and check if bolt patern and other dimensions are a match?
TeZee probably?

Thanks a lot!
Tim

[guyhockley]

My original post has a lot of links to interesting 2T EFI projects like this one:- EFI CR250 https://youtu.be/VlHyRcmlLgU

http://www.supermototecnica.<wbr>com/2015/09/10/sviluppi-del-<wbr>sistema-iniezione-diretta-<wbr>indiretta-due-tempi/ (http://www.supermototecnica.com/2015/09/10/sviluppi-del-sistema-iniezione-diretta-indiretta-due-tempi/)



Seen this one, already?

http://www.snowmobile.com/products/fuel-injection-systems-in-todays-twostroke-600s-1775.html

[guyhockley]

https://www.kiwibiker.co.nz/forums/images/BP-Brown/misc/quote_icon.png Originally Posted by husaberg https://www.kiwibiker.co.nz/forums/images/BP-Brown/buttons/viewpost-right.png (https://www.kiwibiker.co.nz/forums/showthread.php?p=1131048592#post1131048592)
Most of the RGV300s are simply made out of the RG150 cylinders.



No, they are just bored out and replated standard cylinders (with all the compromises that brings)

Certainly the case in the UK, but then we have RG125s to suit our licensing laws.

[guyhockley]

Just found these.

[guyhockley]

and a few more.

[2T Institute]

Gordon Jones had a set of rgv 350 cylinders that got sold to Richard Vanagas in the UK. I know where some TZ/TZR 350 Hummel cylinders/heads are for sale

[husaberg]

No, they are just bored out and replated standard cylinders (with all the compromises that brings)


[IMG]

Certainly the case in the UK, but then we have RG125s to suit our licensing laws.
Thats just silly much easier to use RG150 (i know the UK had them as Grey imports) ones or better yet modded Artic Cat ones

I have a question: Does an owner of a Honda NSR250 cylinder or head may print this out
331151
and check if bolt patern and other dimensions are a match?
TeZee probably?

Thanks a lot!
Tim

I can't see youtr picture but nsr125 heads don't bolt on to NSR250 even though the cylinders can be fitted to each other


RG crank centre is quite different to the RGV, is it easily interchangeable?
Here's a Hummel 375 with a 54mm crank:
http://www.geckomotorcycles.co.uk/magento/4dp-3xv-yamaha-tz-375cc-hh-big-bore-kit.html

Google vincent crabtree rgv250 big bore
http://www.apriliaforum.com/forums/showthread.php?119747-Rgv250-66mm-350cc-Big-Bore-Kit-E-Mids-UK
http://www.apriliaforum.com/forums/showthread.php?197296-Racing-Crankshaft/page4
https://sites.google.com/site/vpcrabtree/home/suzuki-rgv250-vj21
https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130586696#post1130586696
https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1131030948&highlight=rg250#post1131030948
i have some stuff he sent me somewhere as well.
He seems like a nice fella, i think hes a doctor or something similar
i posted it on this thread in reply to a question from either sketchy racer or Richban




Gordon Jones had a set of rgv 350 cylinders that got sold to Richard Vanagas in the UK. I know where some TZ/TZR 350 Hummel cylinders/heads are for sale
You were going to try modding a RG250 crank to go in a RGV weren't you?


In one video (can't recall which though) it was mentioned that it might be a Mikuni patent and that is also the reason they switched to Mikuni carbs for the '17 models.
Yeah i seen that also it was in a link i post about 10 days ago.

I do not understand how any firm could obtain a patent, for a technique where there are clearly examples of people who experiment with variations on the same theme since years...
Is this bluff poker from KTM ?

pretty anyone can patent something as long as its novel and they pay the fee, it doesn't have to be their idea, they can also buy the pattent licence
History is littered with people stealing and patenting others ideas RCA used to do it big time with TV ad Radio.

[Flettner]

Yes but if it's 'prior knowledge' ie been in public view, not secret (250,000 views on just one YouTube clip) then it can not be claimed as novel. I don't care what KTM do so long as they don't stand on my toes when I build my commercial run of engines :bleh:
Anyway I'm sure if I get to that point I'll have a mark three system. All these patented systems we are looking at deliver the fuel toward the piston or directly into the lower cylinder. Our YZ is the only one that points the injectors discharge at the incoming transfer flow. Best air fuel mixing and somewhere to store the extra fuel when the injectors on time exceeds port open time, or at least usefull gas flow time. Remember the delay in injection is only at lower engine speeds where short circuting is worst. Further more I think that at higher engine speeds there is an amount of fuel that finds its way into the A ports because there is a time when there is no port airflow but the injectors are firing, fuel get into the A port inlet. The first gas out of the A port into the cylinder is just air then the fuel behind it. That's why KTM are using this system, I'm sure they have worked this out also.

[guyhockley]

Could be the KTM patent?

https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2015113096

Roland Kirchberger is a university professor so possibly a bit like Blair at QUB, maybe.

[koenich]

as husa and mols pointed out, patents are a hole other animal. the claims could just consist of some details and thats it...:rolleyes:

[Frits Overmars]

I do not understand how any firm could obtain a patent for a technique where there are clearly examples of people who experiment with variations on the same theme since years...Patent bureaus should investigate whether an idea is really original, before they grant a patent. But it seems that sometimes they don't bother: you get your patent and if it appears that you weren't the first, that's too bad for you: patent null and void, money thrown away. I've seen it happen on more than one occasion.


Could be the KTM patent?
https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2015113096Could be a KTM patent, but not the KTM patent.
two fuel injection nozzles... whose nozzle axes extend... approximately in the outlet flow direction of the overflow channels... on the opposite sides...The above patent specifically states that each injector is aimed at the air flowing out of the opposite transfer port, which is clearly different from Flettners solution,
and also different from the actual KTM TPI implementation.

[guyhockley]

Patent bureaus should investigate whether an idea is really original, before they grant a patent. But it seems that sometimes they don't bother: you get your patent and if it appears that you weren't the first, that's too bad for you: patent null and void, money thrown away. I've seen it happen on more than one occasion.

Could be a KTM patent, but not the KTM patent.The above patent specifically states that each injector is aimed at the air flowing out of the opposite transfer port, which is clearly different from Flettners solution,
and also different from the actual KTM TPI implementation.

Confession time - didn't have time to read it, posted it on the basis of the drawing... tea break, now. I'll have a proper look!
Oh, yeah, just looking at the other drawings, it's patently different (see what I did there?!)

[husaberg]

Patent bureaus should investigate whether an idea is really original, before they grant a patent. But it seems that sometimes they don't bother: you get your patent and if it appears that you weren't the first, that's too bad for you: patent null and void, money thrown away. I've seen it happen on more than one occasion.

Could be a KTM patent, but not the KTM patent.The above patent specifically states that each injector is aimed at the air flowing out of the opposite transfer port, which is clearly different from Flettners solution,
and also different from the actual KTM TPI implementation.

Have a look at this and all the citing and referenced patents
https://www.google.com/patents/US6691649

[jamathi]

Are 'big bore' cylinders really that good?
At Aprilia some of the boys working with me fitted big bore cylinders to their Rotax engined bikes.
The result was always the same: less power.....
Because of the big bore made a mess of the transfer ducts!

[husaberg]

Are 'big bore' cylinders really that good?
At Aprilia some of the boys working with me fitted big bore cylinders to their Rotax engined bikes.
The result was always the same: less power.....
Because of the big bore made a mess of the transfer ducts!

likely true Jan an engine should be designed and engineered for its size, to limit space compromises.
The class where i was discussing their racing use is NZ F3. (Yeah i know its not the name now)
Due to a rule change a few years ago it now allows 2t multis up to 400cc as long as they have road based crankcases.
GP bikes are only allowed to be 125's
As most of the later 2T bikes are 250cc such as RGV250 or NSR250 this is why they go the big bore route.
the 4ts they compete against are 450 multis old VFR400's bored out etc plus 600/4 with one cylinder disabled. \or 650 twins SV650 etc
The RZ350 is one option Wob has done. He was also doing a NS400 with cr based cylinders for someone
I think you might have gone with the RG400 which is the small bore version of the RG500.

[Lef16]

Jan, can you tell us about the cylinder casting(aluminum type,casting procces,heat treatment after etc)?

[Tim Ey]

Are 'big bore' cylinders really that good?
At Aprilia some of the boys working with me fitted big bore cylinders to their Rotax engined bikes.
The result was always the same: less power.....
Because of the big bore made a mess of the transfer ducts!

Hi Jan, if you refer to the Polini cylinder for the Rotax 122 and 123 - the lower Power is caused by reduced port timings compared to Rotax barrels.
The timings are still quite low when you combine the Polini for the 123 with a 56mm crank. Without spacering the head insert...

[Tim Ey]

I can't see youtr picture but nsr125 heads don't bolt on to NSR250 even though the cylinders can be fitted to each other

That was a PDF. Did work for me?!
Anyway, this is the picture of the head I want to build.
331161
Would be interested if NSR250 is a match and I do not need to do the CNC Milling.

Regards
Tim

[monkeyfumi]

Thats just silly much easier to use RG150 (i know the UK had them as Grey imports) ones or better yet modded Artic Cat ones

Have you tried finding RG150 or arctic cat cylinders? Absolute hens teeth compared to standard RGV250 (especially as most people use the ones they already have on the bike)

Off the shelf kits using 250 cylinders have been sold by a couple of places, 150 or arctic cat is all DIY.

As I said, it's all a big compromise anyway, as it makes an already oversquare engine more so, and as Jan commented, takes a big chunk out of the transfer ducts.

[1948rod]

Have you tried finding RG150 or arctic cat cylinders? Absolute hens tehieth compared to standard RGV250 (especially as most people use the ones they already have on the bike)

Off the shelf kits using 250 cylinders have been sold by a couple of places, 150 or arctic cat is all DIY.

As I said, it's all a big compromise anyway, as it makes an already oversquare engine more so, and as Jan commented, takes a big chunk out of the transfer ducts.

Hi I had hoped that I could use to 350 Pistons in the spare cylinders on my tza 250 engine hoping it would have better torque for hill climbing or second choice big bore on my rev. I wouldn't modify the Tz cases so it could be reused for historic bike races.

[wobbly]

Does anyone know of a TZ250G cylinder that is unusable.
I want to section one up the Ex port to look at whats needed for to add Aux for a LSR engine.

[kel]

I have a question: Does an owner of a Honda NSR250 cylinder or head may print this out
331151
and check if bolt patern and other dimensions are a match?
TeZee probably?

Thanks a lot!
Tim
No they are not a match. See attached NSR250R MC21 cylinder and head gasket photos.

[2T Institute]

Thats just silly much easier to use RG150 (i know the UK had them as Grey imports) ones or better yet modded Artic Cat ones


I can't see youtr picture but nsr125 heads don't bolt on to NSR250 even though the cylinders can be fitted to each other



Google vincent crabtree rgv250 big bore
http://www.apriliaforum.com/forums/showthread.php?119747-Rgv250-66mm-350cc-Big-Bore-Kit-E-Mids-UK
http://www.apriliaforum.com/forums/showthread.php?197296-Racing-Crankshaft/page4
https://sites.google.com/site/vpcrabtree/home/suzuki-rgv250-vj21
https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130586696#post1130586696
https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1131030948&highlight=rg250#post1131030948





You were going to try modding a RG250 crank to go in a RGV weren't you?




Yes just the cylinder to do. Though I have seen in Italy a fellow fitted RS honda cylinders. RM 125 would be a good start

[TZ350]

331181

MC21 stud pitch circle is 88mm, outside diameter 104mm with studs evenly spaced.

The MC18 is different to the 21 and the NSR125 has an uneven spacing of the studs compared to the 18.

[2T Institute]

Are 'big bore' cylinders really that good?
At Aprilia some of the boys working with me fitted big bore cylinders to their Rotax engined bikes.
The result was always the same: less power.....
Because of the big bore made a mess of the transfer ducts!
Have made a 288cc Rotax that was 6 hp/4 ft/lbs torque more than the 250cc that diminished down to the same peak power at the same rpm. A full 350 is under construction. Big bores tend to make way more mid range.

[2T Institute]

Does anyone know of a TZ250G cylinder that is unusable.
I want to section one up the Ex port to look at whats needed for to add Aux for a LSR engine.

Contact Craig Stafford on FB his dad Don was a Yamaha dealer for many years and was recently selling a big box of that era TZ stuff

[Ocean1]

Does anyone know of a TZ250G cylinder that is unusable.
I want to section one up the Ex port to look at whats needed for to add Aux for a LSR engine.

Is it difficult to justify this?:

https://www.dotmed.com/listing/ultrasound-general/microscribe-3dx-desktop-digitizer-transducer-probe-articulated-arm/microscribe-3dx/2281218

[husaberg]

Have you tried finding RG150 or arctic cat cylinders? Absolute hens teeth compared to standard RGV250 (especially as most people use the ones they already have on the bike)

Off the shelf kits using 250 cylinders have been sold by a couple of places, 150 or arctic cat is all DIY.

As I said, it's all a big compromise anyway, as it makes an already oversquare engine more so, and as Jan commented, takes a big chunk out of the transfer ducts.

Ebay is full of zrt600 arctic cat cylinders.
for the RG150 cylinders try the asian countries where they were sold. Like Thailand
NZ had quite a few, More than the 125's but the 150 streetstock racing class has swallowed them.

[monkeyfumi]

Ebay is full of zrt600 arctic cat cylinders.
for the RG150 cylinders try the asian countries where they were sold. Like Thailand
NZ had quite a few, More than the 125's but the 150 streetstock racing class has swallowed them.

A moot point, as I'm not interested in big bore kits. Just wanted to correct your assertion that RGV300 are usually done with 150 cylinders, when overwhelmingly, they are not.

[Flettner]

Ha Ha, I guess the best way to get in contact with KTM is to announce a production run of modified cylinders with TPI to suit the YZ 250. I'm sure I'd get a letter then:devil2:

[Frits Overmars]

331185
All the best, mate!

[tjbw]

331185
All the best, mate!

Happy Birthday Jan

[peewee]

best wishes jan and thnx for the contributions :first:

[EssexNick]

Happy birthday. I'll raise a glass to you tonight in the pub.

[husaberg]

Happy Birthday Jan
331192

[Greg85]

Happy Birthday Jan

Happy birthday Mr Jan Thiel

[JanBros]

gelukkige verjaardag Jan :wavey:

[peewee]

hey guys I got the com ratio lowered from 19.5 to 16 by raising the bowl 1.5mm instead of cutting out more and risking a crack and water leak. kicks over far easier and with the compression release activated its no more difficult than a moped :wings:

[F5 Dave]

Just striped the TF125. Sodding offset spark plug. apart from the travety, how am I going to machine it? Sucky.

[lodgernz]

Just striped the TF125. Sodding offset spark plug. apart from the travety, how am I going to machine it? Sucky.

Can you turn some of the head out and fit an insert with a central plug?

[peewee]

ive seen people cut out the chamber and fit a insert. youll have to get everything right so the orings don't leak. could probly also cut open the top and do some welding where needed to plug the old hole and establish a central located one

[TZ350]

Happy Birthday Jan
331192

Plus...1 and thanks you for your knowledge and contributions.

[F5 Dave]

Insert in aircooled head not so advisable as LC. Its all comprises this thing.

[Muciek]

Jig like that?

331203331204

[F5 Dave]

Should, we'll see, there's plenty else to do and I don't want it cconsuming all spare time for my own projects. At least head falls off pretty quick, can be done later in between race meets if it needs optimising. Wonder if I can find a straight plug head to adapt on?

[husaberg]

Should, we'll see, there's plenty else to do and I don't want it cconsuming all spare time for my own projects. At least head falls off pretty quick, can be done later in between race meets if it needs optimising. Wonder if I can find a straight plug head to adapt on?

It looks like the other TS125er and DS125 both have angled plugs as well.

[Ocean1]

It looks like the other TS125er and DS125 both have angled plugs as well.

TM125 had twin plug holes, one central, same bolt spacing?

Mind you, a mate cast his own TM heads because of the funny chamber shape that caused...

[husaberg]

TM125 had twin plug holes, same bolt spacing?

Mind you, a mate cast his own TM heads because of the funny chamber shape that caused...

No, they changed to a 4 bolt pattern on the case reed versions.
Dave could weld it up as the squish band likely needs some work also
But to be fair, most immediate gains of the go fast stuff might be better served on the porting and exhaust.

[F5 Dave]

Yeah I think get the thing going and out of my garage and then weld a head up.

[TZ350]

Yeah I think get the thing going and out of my garage and then weld a head up.

Get it going and out on the track, improvements later is probably a good plan.

If you have a DC-CDI Race 2 Ignitec (originally for the RGV250) you could run twin plugs and coils firing together in the TF head.

[TZ350]

MAP sensor measuring pressure in the Expansion chamber.


Following Nath88's thoughts on expansion chamber resonance wave collapse below 20% throttle and Flettners suggestion to detect the collapse by measuring the pipes internal pressure at the parallel dewell mid section of the pipe I installed a pressure tap and tube for the EFI's MAP sensor.

To see what if anything the MAP sensor would register I could only manage a few blips of the throttle before the smoke in the garage became to much and the noise was likely to annoy the neighbours.

331207

It was only a quick few blips of the throttle, but enough to show the MAP sensor was recording Ok and the changes in the pipe pressure look like they could be used to tell when there was resonant wave action in the pipe drawing air through the motor and more fuel required or not.

It will be a week or so before I can get it on the dyno so plenty of time to tidy the arrangement up and add a few options like SwePatrick has to his drag bike for smoothing the pressure pulses out.

[Nath88]

Looks like it should work. Keen to see how it goes.

I've just relocated my MAP sensor closer to the pressure take off in the header. Hopefully the heat doesn't kill it, overall hose length is much shorter now, so the delay over the hose should be less of an issue.
331210
My attempts to modify the ecu code to measure the maximum pressure in the sample window rather than the minimum have been unsuccessful, so I'm inverting the output of the MAP sensor with an op-amp. Maybe problem solved, will test in a few hours.
331211

[TZ350]

Inverting the signal, good idea, looking forward to seeing the results.

[peewee]

everything hooked up and ready to go. I hope to try it this weekend and get video :laugh:

[TZ350]

Ecotrons BlueTooth Adaptor.

331220

Ecotrons make a BlueTooth add on device for the EFI CPU so that you can connect to it with a smartphone and easily record real world running data as you ride around with the phone in your pocket.

331219

The phone could be in your pocket or mounted somewhere that you can see it and watch the data as it's recorded in real time. It was pretty straightforward to set up. After a run the data from the phone is copied over to a PC and displayed using the Ecotrons EFI reporting software.

331221

A sample of a quick data grab I did this afternoon from a couple of blips on the throttle. Should be useful when I get to take the bike to the track or someplace quiet for a bit of run. Hopefully it will be helpful in sorting out what is needed when the throttle is closed after a fast run then opened up again. Like when slowing for a corner and then pulling away again.

Everything else about the power and tunability of the EFI system on my bike is great but it is this throttle off and on again that has held me back from being able to successfully use it with the 2T.

[TZ350]

everything hooked up and ready to go. I hope to try it this weekend and get video :laugh:

Good luck, I am looking forward to seeing the vid.

[peewee]

if it holds together then maybe swepatrick can advise me how to use 10% nitro :eek:

[teriks]

MAP sensor measuring pressure in the Expansion chamber.


Following Nath88's thoughts on expansion chamber resonance wave collapse below 20% throttle and Flettners suggestion to detect the collapse by measuring the pipes internal pressure at the parallel dewell mid section of the pipe I installed a pressure tap and tube for the EFI's MAP sensor.

To see what if anything the MAP sensor would register I could only manage a few blips of the throttle before the smoke in the garage became to much and the noise was likely to annoy the neighbours.

331207

It was only a quick few blips of the throttle, but enough to show the MAP sensor was recording Ok and the changes in the pipe pressure look like they could be used to tell when there was resonant wave action in the pipe drawing air through the motor and more fuel required or not.

It will be a week or so before I can get it on the dyno so plenty of time to tidy the arrangement up and add a few options like SwePatrick has to his drag bike for smoothing the pressure pulses out.
You are closing on what have been done in the RC size engines since forever, only much more complicated ;)

The brute approach we use, as Im sure you are aware of, is to pressurize the tank from the pipe, using extremely rudimentary carbs without any fancy stuff like floats of pumps. Actually, in F3D that I fly the carb is no more than a venturi, spraybar and a needle valve, not even a throttle..

Anyway, with that brute approach the position of the pressure tap is a variable to play with. When on the dwell/belly section of the pipe, the sudden pressure increase when getting on the pipe can cause an immediately rich condition (no throttle, so starting is done with the needle valve extra rich) making it difficult the get the engine "on the pipe". If that's the case, one way to reduce the problem is to move the pressure tap a couple cm forward onto the divergent cone.

Now this might not be of any use at all for you, at least not at the moment.. perhaps some day...

[TZ350]

... difficult to get the engine "on the pipe". If that's the case, one way to reduce the problem is to move the pressure tap a couple cm forward onto the divergent cone.


Thanks Teriks, very interesting. Could be helpful in solving the 2T EFI issues. KTM have done it for the bigger slower reeving 2T bikes but not saying how of course. I hope we can solve it for the smaller high reeving 2T's so it becomes general knowledge for anyone interested in exploring 2T EFI for themselves.

[jonny quest]

Has anyone tried the Brisk 360 degree firing spark plugs?

[F5 Dave]

Had a look on their site. Multi spark.

Some constants; there is only so much energy and a spark will take path of least resistance.
Open air test vs in a chamber compressed with gas may look different.
Makes for a cool video but slowed down will you see just one spark for each event? If so there doesn't seem much point, and if it was multiple sparks they would divide the energy.
So you are left with no shrouding as only advantage I see.

[husaberg]

So you are left with no shrouding as only advantage I see.

Not sure about that one or know anything about any of the brisk plugs, but pretty sure i have seen it mentioned that the Competition "shorty" plug is a heck of a lot cheaper than the NGK version.
I doubt that includes shipping them to NZ in euros though.


Fascinating to watch that transition!
.

In case any one is wondering what has happened to Adegnes.
It seem he has been watching far to many re runs of Sons of Anarchy.

https://www.youtube.com/watch?v=--mmcxNH67g
The Vice grip side stand is awesome, what's the headlight.

[adegnes]

In case any one is wondering what has happened to Adegnes.
It seem he has been watching far to many re runs of Sons of Anarchy.

https://www.youtube.com/watch?v=--mmcxNH67g
The Vice grip side stand is awesome, what's the headlight.

Thanks Husa! Haven't been posting here for a while and just recently caught up with the conversation.
The headlight is from an old(duh) truck I think, not sure, found it in the woods...
I started this rat scoot project for a couple of reasons:

- Needed something interesting but relatively maintenance free to ride at rallies, The Spx is an ever changing prototype and not very suitable.

- With everything else I've built it's allways been about performance only, by focusing on looks I get to use my brain in a different way which turned out to be alot of fun! Try it!

- I need something to do in the garage on late nights when I can't run the dyno(noise) but there's nothing but dynoing to do with the Spx

- Becoming a badass was way overdue, who needs turn signals when you've got a middle finger!

I'll post an update on the Spx after the next dyno session on methanol/nitromethane.

331236
331237

[dark art]

Has anyone tried the Brisk 360 degree firing spark plugs?

They seem very prone to ceramic cracking at the first sight of detonation...

[Frits Overmars]

They seem very prone to ceramic cracking at the first sight of detonation...I have no hands-on experience with Brisk plugs, but it will be wise to assume that all spark plugs show this behaviour. If a plug has seen detonation, don't use it again. Compare the cost of an extra plug against the cost of a piston, a cylinder, a head and a plug...

[FastFred]

- Becoming a badass was way overdue, who needs turn signals when you've got a middle finger!

331237

Totaly love it! .... :niceone:

[TZ350]

Me 2 plus+1 .... :jerry:

[wobbly]

This is the very reason the only plug I will use is the R7376.
The normal Iridium plugs dont have the rare earth ground strap, and it is not laser welded on - more spark energy needed and then it falls off.
The same plugs crack the ceramic at the slightest hint of deto, never seen this happen on the R7376.
The 5K resistance fails regularly on other plugs, going open circuit - never seen that either.
There is a reason the shorty plug is a stupid price,luckily the R7376 is the same nose configuration but is made in sufficient numbers to reduce the cost.
And no the competitions plug with supposedly the same nose, makes less power every time I have tested this, and that has been enough times to be conclusive.
Any plug be that the Brisc, or even the wank Splitfire things,are all a waste of time due to not having both rare earth electrodes.

[lodgernz]

Wobbly, do you have any recommendation for a 10mm 19mm reach resistor plug of the same sort of quality as the 7376?
R0373A? R0045Q?

[F5 Dave]

Well I can say with some confidence that the B7HS that came out of this TF isn't going back in. :rolleyes:

[wobbly]

I have used R0373A before with no issues, it has an Iridium electrode and platinum ground strap the same as the other expensive types.

[lodgernz]

I have used R0373A before with no issues, it has an Iridium electrode and platinum ground strap the same as the other expensive types.

Thanks Wobbly. I'll start saving...

[richban]

They seem very prone to ceramic cracking at the first sight of detonation...

It seams they are prone to ceramic cracking det or not. I tried some in the 300 NSR and both cracked.

[peewee]

Good luck, I am looking forward to seeing the vid.

earlier in the day it would clean out and run pretty good then I went to a different spot and with same carb settings it loads up bad. turned one of the powerjet in alittle but maybe it needs to go more is the only thing I can think but I don't understand why it wouldn't run nearly the same. when I get it sorted out and running good I want to try nitro 10%. also I have some 2.5"x2.5"x16" chunks of 6061 to make swingarm extensions one of these days :cool:





https://www.youtube.com/watch?v=zLRMN1RLM6A




https://www.youtube.com/watch?v=yqqi10ZQXRg

[SwePatrick]

earlier in the day it would clean out and run pretty good then I went to a different spot and with same carb settings it loads up bad. turned one of the powerjet in alittle but maybe it needs to go more is the only thing I can think but I don't understand why it wouldn't run nearly the same. when I get it sorted out and running good I want to try nitro 10%. also I have some 2.5"x2.5"x16" chunks of 6061 to make swingarm extensions one of these days :cool:





You running methanol?

[TZ350]

when I get it sorted out and running good I want to try nitro 10%.:cool:


Yummm Nitro, yum yum..... :yes:

[TZ350]

331288 ... SSDD ...

Same Shit Different Day

Well all I wanted to do was try and see if the EFI software could see pressure changes in the expansion chamber and if so if I could do something useful with them.

The standard no porting modifications NSR cylinder was making a reliable upper mid twenty's very usable HP.

But I couldn't help myself and got stuck into a spare cylinder with the porting tool and leveled the top of the exhaust port off and ground the PV blades to suit. The extra blow down time area should be good for another couple of hp.

I also made a oval to round nozzle transition like Wobbly describe. I must not understand what Wob means because the new cylinder and nozzle made way less power than the standard cylinder. Disappointing but not a surprise, try something new and some of the horses always seem to bolt and go AWOL for a while to start with. So Nozzle or ported cylinder??? not sure which is the problem but changing out the nozzle was the easiest.

Next night I swapped out the nozzle for the original straight through adapter and ran the bike up on the dyno expecting better things. But no, same shit different day. Now the beast can hardly pull the skin of a rice pudding and fell over at 8,000 rpm, lean as bat shit. I pored in more fuel 20%-50-100% and more, whatever I tried it still dropped dead at 8k or so.

So now I have a list of things to check:- chrome pealed of the bore, massive air leak at the adapter, maybe one of the high speed fuel injectors has dropped dead, EFI software calibration file has become corrupted, that's happened before. Trigger coil playing up, ignition coil/cap breaking down, bad plug. If these problems were real shit this bike would have diarrhea.

Anyway I am no closer to knowing if the EFI software can see changes in the internal pressure of the expansion chamber.

Maybe I will get there tomorrow night...... :(

[jonny quest]

Probably would be wise to put on your original test cylinder

[peewee]

You running methanol?

yes vp M1. do you have some good advise ? :cool:

[Grumph]

yes vp M1. do you have some good advise ? :cool:

Get yourself a water content testing kit - and use it frequently.

[SwePatrick]

yes vp M1. do you have some good advise ? :cool:


Actually yes.

I dynoed mine 211 cc engine this weekend, a drop in peak power from earlier.
But it was expected as i have been aiming for wider powerband.
61.86hp at the wheel and 36.11nm, average power is 41.79hp from 6000rpm to 13000rpm.

However, my first advice is make sure spark is in center of combustionchamber in all axis, XYZ.
Index sparkplug carefully 'opening' towards boost.
Then check your reed petals, i had a brand new v-force3 to test.
16 pulls and the petals were soft as rubber.
Best power and torque however with my heavily modified boyesen radvalve.
0.45mm polini carbonit petals with no additional blades at all, no dampening petals either.
std it's a '4 blade' setup, i´m running two big blades.
Ported a lot and welded it straight(straight shot for the carb into cylinder)

Try to map down where the engine is lean or fat in throttleregister.
Then modify your meteringrod/needle in carb to suit this.
Mine is very very crisp in lower throttleopenings, this doesn´t wet down the crankcase at all(no need to rev it clean).
But i also as is running a Keihin PWM carb, they´ve got a separate idlesystem, i can let it be very lean on idle.
As for now i run '100' jetsize on lowspeed and '245' on highspeed, and my homemade powerjet is fully open, dunno the flowrate on that.
Powerjet is also located from bottom and up a third of carb bore.
This to react early and maybe lean out more at top

There are some more hp lurking in my engine as i´m a bit small on the carb(40.5mm as we speak)


So my main advice is: spend a lot of time get the fuel distribution correct.

Rgds.

[G Jones]

Closer to (my) home, the F350 sidecar class now seems to be flooded with Banshee motors, but, previously, there were Yam V-twin 350s and at least one competitor (John Crick?) had a 350 RGV. Some, or all, of these may have come from George Hardwick (GHR) who has unfortunately now died and his website is gone as well.
NB. I've no involvement or experience with F350 so the above is just based on reading reports in BSN, perhaps Mr Jones may correct me if I've misremembered.
OK - been a bit busy so missed this...
I think "flooded" would be a slight exaggeration - lucky to get 2 or 3 bikes turn up these days - there was one reasonably successful guy running a Banshee motor - which was originally built by a well known UK "tuner" as a hill climb bike at something like 525cc capacity - that was running in our series as a 350...
That bike has now been sold to a guy - I think in Sweden...
As far as I know - the GHR was a V twin TZ with 350 cylinders made by George - the current owner ran it for the 2010 season - far as I know - not been run since - 2010 was the last season we had a credible turn out of 2 strokes in the UK - only place we can get a race is in Europe now - the UK series was modified to try to get more people interested (due to falling grids) - you can now run anything with carbs - so a 350 TZ is not anywhere near....
Just for information - there is another George Hardwick bike that makes an occasional appearance in the uk - that one has a Hon*a twin of around 500cc in it - didn't look that close due to it's heritage - sooner stick rusty needles in my eyes than look closely at a Hon*a...

The Aprilia / Suzuki V twin that John Crick ran for a while - I bought the whole bike / spares - everything...it had a reputation for being fast but "fragile"
After a while of looking it over - the chassis I decided I couldn't work with - too many compromises for my own liking - so I sold it & carried on making my own (now completed)
The engine - no doubt - could have done something with it - but as I'm an old bastard already - didn't really expect to live long enough for it to be worth the effort - and the short stroke seemed to be the exact opposite of where my thinking was leading me....better for me to stick with what I know (TZ350) - we have well proven parts for everything - engine / gearbox / clutch - all readily available - crankcases too from road bike engines....


Gordon Jones had a set of rgv 350 cylinders that got sold to Richard Vanagas in the UK. I know where some TZ/TZR 350 Hummel cylinders/heads are for saleI had a few people interested in those parts - including you and Richard - in the end I bundled the whole lot up onto a pallet & sent it to a guy in Ireland - far as I know he's in the process of building it into a solo at the moment - sure he'll let me know when it's up and running - last contact I had was when I sent him a few sets of pipes I had kicking around....

Right - back to wasting a load of time making a forced air crankcase cooling duct for the TZ....

[TZ350]

,

Ok got it going, pulled one of the high speed injector plugs off and things improved immediately. Turns out that the excess lean that only got leaner however much I enriched it was because the oxygen left from over rich misfiring made things look real lean to oxygen sensor.

Not as good as hoped but getting close to the same sort of power as the old air cooled motor.

331297

Blue line, unmodified NSR cylinder, Red line, cylinder with the top edge of the exhaust port leveled off for more blowdown time area. Hmmm that didn't work as well as hoped. Found this before, when you create more blowdown time area than required for the engine speed you lose power everywhere and gain little anywhere, it is a real fine line.

Tonights effort was to find out what sort of changes in pressure signal can be seen in the mid section of the expansion chamber.

331298

TPS, Yellow line, RPM Blue line and the Pink line is Map 998.4 to 1126 hPa's as measured at the dwell section of the expansion chamber... a difference of about 0.019 psi. Sure does not seem much.

[G Jones]

Any thoughts on crankshaft mass desirability ?
Reason for asking - I just happened upon some crankshaft pictures - mainly for Italian scooters - seems to be quite a few being sold of what they describe as "Bell Type" - similar to the picture - any other thoughts on any disadvantages - or indeed advantages ?
331300

[Jannem]

My first post here. :) Great thread and learned already a lot by reading....

Perhaps a somewhat noob question, but how straight you can cut single ex-port opening roof? Aiming in the ballpark of 70% (perhaps little over) port width with rounding in the port to bore edge (approximately 2mm radius). 44mm bore.

Any rule of thumb to go by?

[EssexNick]

I've been wondering about this for some time. Pros: might be more case volume. Maybe better big end lubrication. Cons? Might cause more drag. I'm only guessing here, we need the wise ones.

[TZ350]

... how straight can you cut single ex-port opening roof? Aiming in the ballpark of 70% (perhaps little over) port width with rounding in the port to bore edge (approximately 2mm radius). 44mm bore. Any rule of thumb to go by?


Exhaust Port shape for ring life.

314807


The post above links back to pictures originally posted by Frits that talk about port shape. Click on the little blue arrow thing or use "Thread Tools" at the top of this page to view all the images that have been posted on this thread, there are hundreds of them.

331301

[Haufen]

My first post here. :) Great thread and learned already a lot by reading....

Perhaps a somewhat noob question, but how straight you can cut single ex-port opening roof? Aiming in the ballpark of 70% (perhaps little over) port width with rounding in the port to bore edge (approximately 2mm radius). 44mm bore.

Any rule of thumb to go by?

There is a rule of thumb, or more than one. But if you follow it blindly it might leave you with a damaged engine in the end.

I'd make that a bit dependant on the drilling bits you have available. It is far easier to make a radius of 5mm with a bit that is 10mm in diameter than with one which is 7mm in diameter. Are you sure you need an exhaust port that wide? No time to go step by step (and probably learn much more during the process)?

Other parameters influencing the port shape and max. width are:

cast iron bore or plated aluminum bore? If the latter: are you going to replate after grinding?
piston ring pin position (ideal: centerline midle of boost port).
Piston ring thickness (thin is better) and material (less width for cast rings).

[wobbly]

Full circle cranks are the only way too go.
Only kicker to this is the possible scenario where there is no other option when looking for a big case volume increase.
The porckchop cranks have hideous " windage ".
Use full circle with plenty of alloy inserts to reduce the overall mass ( without affecting the beam strength needed to hold the pin and axle rigidly ) along with
alot of small Mallory inserts opposite the pin to get back the balance factor and increase the inertia.
Look at an Aprilia or a factory special TM KZ to see whats needed.

Re single Ex port width and shape - all depends upon the bore and ring width/depth ratio.
Your usual 54mm and above bore is limited to a max of 72%, below 50mm safe ports have been done at 75%.
Frits drawing tells you all you need to know about the shape, but the more you fill in the bottom corner radi,the less A port short circuiting occurs - way more
important than Ex Port STA.

[peewee]

Actually yes.

I dynoed mine 211 cc engine this weekend, a drop in peak power from earlier.
But it was expected as i have been aiming for wider powerband.
61.86hp at the wheel and 36.11nm, average power is 41.79hp from 6000rpm to 13000rpm.

However, my first advice is make sure spark is in center of combustionchamber in all axis, XYZ.
Index sparkplug carefully 'opening' towards boost.
Then check your reed petals, i had a brand new v-force3 to test.
16 pulls and the petals were soft as rubber.
Best power and torque however with my heavily modified boyesen radvalve.
0.45mm polini carbonit petals with no additional blades at all, no dampening petals either.
std it's a '4 blade' setup, i´m running two big blades.
Ported a lot and welded it straight(straight shot for the carb into cylinder)

Try to map down where the engine is lean or fat in throttleregister.
Then modify your meteringrod/needle in carb to suit this.
Mine is very very crisp in lower throttleopenings, this doesn´t wet down the crankcase at all(no need to rev it clean).
But i also as is running a Keihin PWM carb, they´ve got a separate idlesystem, i can let it be very lean on idle.
As for now i run '100' jetsize on lowspeed and '245' on highspeed, and my homemade powerjet is fully open, dunno the flowrate on that.
Powerjet is also located from bottom and up a third of carb bore.
This to react early and maybe lean out more at top

There are some more hp lurking in my engine as i´m a bit small on the carb(40.5mm as we speak)


So my main advice is: spend a lot of time get the fuel distribution correct.

Rgds.

ok thnx. plug is central located on all axis. #9 heatrange. I haven't index the spark gap to the cylinder rear but ill look into it

reeds are brandnew carbon fiber at .4mm thickness with no stiffners. reed block is ktm with some dividers removed for 4 large petals instead of 8 small

carb is lectron 48mm with 2 powerjet. only adjustment is needle length and powerjet. ill try again Saturday to reduce the powerjet fuel. maybe the needle is flooding the crankcase at low engine speeds also

do you have unburnt fuel from the tail pipe ?

[SwePatrick]

ok thnx. plug is central located on all axis. #9 heatrange. I haven't index the spark gap to the cylinder rear but ill look into it

reeds are brandnew carbon fiber at .4mm thickness with no stiffners. reed block is ktm with some dividers removed for 4 large petals instead of 8 small

carb is lectron 48mm with 2 powerjet. only adjustment is needle length and powerjet. ill try again Saturday to reduce the powerjet fuel. maybe the needle is flooding the crankcase at low engine speeds also

do you have unburnt fuel from the tail pipe ?

Just a small amount when cold.
When it is hot, just moisture(oil) like an normal petrolengine.
I gained huge amount of torque with my ported boyesen reedcage.
There is a lot of meat in those to get the shape you want.

Why i advice to index plug is as it seems to run more clean, more crisp more response.
seems to be more important than on petrol.

[guyhockley]

OK - been a bit busy so missed this...
I think "flooded" would be a slight exaggeration - lucky to get 2 or 3 bikes turn up these days - there was one reasonably successful guy running a Banshee motor - which was originally built by a well known UK "tuner" as a hill climb bike at something like 525cc capacity - that was running in our series as a 350...
snip


I did carefully say that I didn't know what I was talking about! Thanks for jumping in.
Thanks too for the "tuner" comment - thought it was just me who didn't think he was some kind of 2 stroke genius...

[guyhockley]

Any thoughts on crankshaft mass desirability ?
Reason for asking - I just happened upon some crankshaft pictures - mainly for Italian scooters - seems to be quite a few being sold of what they describe as "Bell Type" - similar to the picture - any other thoughts on any disadvantages - or indeed advantages ?
331300

Some Vespa cranks are like that because that's the induction system, of course...
Not without precedent for TZs, though. The third picture is from a later article so the, not very clear, crank picture should show what he ended using i.e. pork chop outer wheels and giving up on the split crank idea.

[G Jones]

I did carefully say that I didn't know what I was talking about! Thanks for jumping in.
Thanks too for the "tuner" comment - thought it was just me who didn't think he was some kind of 2 stroke genius...Well - I didn't mention any names but you instantly knew my train of thought ?
Thanks for the (french) article - pity my schoolboy french is too many years ago - although I can pick up some interesting thoughts - the pork chop thing would appear to be an easy way to gain some case volume - although as Wobbly says - full circle is better - it may be possible to slim the flywheels (on the inside face) to the crank pin depth - and regain balance weight with heavy inserts - although more research needed there to understand whether it's possible to add enough weight in the space available...

[Jannem]

There is a rule of thumb, or more than one. But if you follow it blindly it might leave you with a damaged engine in the end.

I'd make that a bit dependant on the drilling bits you have available. It is far easier to make a radius of 5mm with a bit that is 10mm in diameter than with one which is 7mm in diameter. Are you sure you need an exhaust port that wide? No time to go step by step (and probably learn much more during the process)?

Other parameters influencing the port shape and max. width are:

cast iron bore or plated aluminum bore? If the latter: are you going to replate after grinding?
piston ring pin position (ideal: centerline midle of boost port).
Piston ring thickness (thin is better) and material (less width for cast rings).


Cast iron bore, two rings, pins at the sides of the exhaust port (chord length between pins 35mm), ring thickness ~1mm (can't get more accurate measurement right now), don't know ring material.

Step by step process seems like a sensible way to go...

[Jannem]

Read everything I could find about the "leaning tower" scavenging here. Another Q, perhaps my search skills are not that great.:facepalm:

I'm limited to old style piston with high dome (~20deg near the piston edge. there's 1mm flat before the dome above the rings). Would the aprilia style vertical angles of A&B ports have to be altered upwards by the difference of piston dome angle or kept the same?

[F5 Dave]

So the rules? say you must keep this piston?
Piston, rod, gearbox, really determine the revs you can pull.

[Jannem]

Not the rules, but availability in this size. It's a father-son hobby project and learning experience more than anything else. DIY to see what we get done, instead of the simpler way to shelling out to get the same as everyone else. If we can beat some guys with "stock" parts, all the better. :)

Trying to learn as much as we can, that's why we are here.

[Haufen]

Cast iron bore, two rings, pins at the sides of the exhaust port (chord length between pins 35mm), ring thickness ~1mm (can't get more accurate measurement right now), don't know ring material.

Step by step process seems like a sensible way to go...

Cast iron bore is perfect, as it allows you to make nice radiuses between bore and port all around.
The pin position however is a major drawback. how wide is the port at the moment? It might be worth considering to just radius the port edges if you can not move the pins. Your ring thickness should not be a hindrance for a wide exhaust port (if the pins are moved).
If you have an old ring you can try to bend it (in stroke direction). If it bends, then 70% chordal width should be feasible, if it breaks then 65 is your limit.


Read everything I could find about the "leaning tower" scavenging here. Another Q, perhaps my search skills are not that great.:facepalm:

I'm limited to old style piston with high dome (~20deg near the piston edge. there's 1mm flat before the dome above the rings). Would the aprilia style vertical angles of A&B ports have to be altered upwards by the difference of piston dome angle or kept the same?

Your setup does not sound to be particularly high tech, thus using the RSA as an orientation might not be the best of ideas. From the descriptopn of your engine it sounds to me like some sort of "traditional blueprinting" would be a good idea and already provide a noticeable step up in driving performance.

I would keep the vertical angles the same (I might even have asked the same question here some time ago), even with your 20° piston. Keep in mind that these angles are for a sqare engine configuration and thus the "correct" angle values for a short stroke engine are lower and vice versa for a longstroke engine.

[F5 Dave]

I'd modify to try fit a cheap but big- leap- ahead mx piston. Even if it means matching Conrad. All these parts are cheap to replace once the initial machining is done and end result more reliable.
Engineering beats clever portwork in many respects. That also makes for practical research experience. Let your son find the options and vet together.

Light strong piston with low crown to pin height and thin ring. There's power through alternative part engineering. Else you are just following a well trodden part of std parts and consistent constraints, compromises and breakages if shoddy spinning metal.

Wish I'd learnt that a lot earlier and spent more trying to ignore that lesson to run what I had again and again.

[diesel62]

Hi guys .I have just come across this in a motoring magazine that comes to work
Cant see it working to be quite honest

[adegnes]

Trying to learn as much as we can, that's why we are here.

+1
Best motivation.

[Jannem]

Cast iron bore is perfect, as it allows you to make nice radiuses between bore and port all around.
The pin position however is a major drawback. how wide is the port at the moment? It might be worth considering to just radius the port edges if you can not move the pins. Your ring thickness should not be a hindrance for a wide exhaust port (if the pins are moved).
If you have an old ring you can try to bend it (in stroke direction). If it bends, then 70% chordal width should be feasible, if it breaks then 65 is your limit.



Your setup does not sound to be particularly high tech, thus using the RSA as an orientation might not be the best of ideas. From the descriptopn of your engine it sounds to me like some sort of "traditional blueprinting" would be a good idea and already provide a noticeable step up in driving performance.

I would keep the vertical angles the same (I might even have asked the same question here some time ago), even with your 20° piston. Keep in mind that these angles are for a sqare engine configuration and thus the "correct" angle values for a short stroke engine are lower and vice versa for a longstroke engine.

Port is now 28mm, so there is room. Don't have extra rings to test. Piston is Italian GPM, and appears much more decent quality than the typical far east choices. Rings do not have a coating and look decent, but are magnetic.

It's an AM6 cylinder with Suzuki piston. Stock the transfer timing is at 130deg and blowdown will not be staggering even with raised exhaust. Will see how it all pans out after we get it on the case, but expect to machine the lower end of the cylinder as the piston is little shorter than stock.

The aggregate angle of the piston with the flat at the edge is ~15% and the 44mm is 4mm overbore with 39mm stroke. So the angles may be reasonably close after all. Basic trigonometry says 2mm per side you'd use 3 deg less angle for the new bore with original type piston.
I appreciate the oversquare by boring out is not ideal with the implications to transfers. Two wrongs usually do not equal one right, but in this case higher dome and overbore impact to transfer angles may actually fit somewhat together. I'm however building a angled porting tool to adjust the transfers.


I'd modify to try fit a cheap but big- leap- ahead mx piston. Even if it means matching Conrad. All these parts are cheap to replace once the initial machining is done and end result more reliable.
Engineering beats clever portwork in many respects. That also makes for practical research experience. Let your son find the options and vet together.

Light strong piston with low crown to pin height and thin ring. There's power through alternative part engineering. Else you are just following a well trodden part of std parts and consistent constraints, compromises and breakages if shoddy spinning metal.

Wish I'd learnt that a lot earlier and spent more trying to ignore that lesson to run what I had again and again.

I wholeheartedly agree. I would have liked to use another piston which has much shorter compression height and 10mm longer rod, but it's out of the question because of the budget constraints. Without going into lengthy personal history, I can dedicate much more time than before and very little funding to my kids at the moment. Used to be vice versa. Life has it's surprises and the bad ones may be good ones as well. My 15yr son paid for the bike out of his own pocket and got much better one than he expected, because we could buy one previous owner didn't know how to fix and we did it together.

I have a lot of experience in the 4-strokes, decent tools and even a crude flowbench which can be used to test basic wet flow, but 2-strokes are a learning curve.

[husaberg]

Some Vespa cranks are like that because that's the induction system, of course...
Not without precedent for TZs, though. The third picture is from a later article so the, not very clear, crank picture should show what he ended using i.e. pork chop outer wheels and giving up on the split crank idea.

Pretty much every low powered two stroke up to the mid sixties was that design.
Villiers or a victa lawnmower
I refer to them as being Pork chop cranks.

331331
But They found better power by filling them with all sorts of bits of epoxy or screwed or brazed on lumps.
This was because they had poor port designs and short transfer timing.
Yes large crankcases are in fashion as they work better with modern porting designs.
For instance a TZ350 works better with the larger volume RD400 crankcases.
But the large large modern crankcses still have smooth crankshafts with no cut outs to lesssen turbulence and fiction and pumping losses..
Here are some pictures of how they should look. with 1mm clearance to the crankcase at every dimension
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839&attachmentid=330835
https://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=314110&d=1438074109
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839&attachmentid=314111
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839&attachmentid=314108
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839&attachmentid=314093
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839&attachmentid=312225
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839&attachmentid=311364
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839&attachmentid=311365
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839&attachmentid=303952
https://www.kiwibiker.co.nz/forums/album.php?albumid=4839&attachmentid=303485

[Jannem]

Has anyone tried putting a fin to the exhaust port roof to help with the pressure distribution and reduce the secondary flow to make the port more efficient? The attached CFD picture shows pretty well, what the situation typically is. I've seen it work with compromised intake ports using my flowbench.


331330

[Frits Overmars]

Has anyone tried putting a fin to the exhaust port roof to help with the pressure distribution and reduce the secondary flow to make the port more efficient? The attached CFD picture shows pretty well, what the situation typically is. I've seen it work with compromised intake ports using my flowbench.Jannem, that fin may indeed reduce secondary flow and make the port more efficient. But what your flow bench does not tell you, is how much heat the fin will transfer from spent gases to washed-through fresh mixture.
Any fin is a heat exchanger. Or, as I used to say when I was younger and more sarcastic: "I'd rather have my cooling fins at the outside of the exhaust duct" :devil2:.

[Jannem]

Jannem, that fin may indeed reduce secondary flow and make the port more efficient. But what your flow bench does not tell you, is how much heat the fin will transfer from spent gases to washed-through fresh mixture.
Any fin is a heat exchanger. Or, as I used to say when I was younger and more sarcastic: "I'd rather have my cooling fins at the outside of the exhaust duct" :devil2:.

It indeed is a compromise, as is the single ex-port. Cut and try will tell, or braze in this case. Just thought if someone has tried and would be willing to share findings.

Edit: perhaps another fin on the roof of the port, inside the water jacket could compensate some...

[136kg136ps]

Frits,seeing the words outside cooling above,would it be helpful to have external water cooling on the first few inches of exhaust?I was thinking brass,copper or stainless tubing tightly wound or possibly welded to the header for better heat conduction.Inexpensive and simpler to figure out vs welding up the cylinder to add water passages it would seem.

[Frits Overmars]

perhaps another fin on the roof of the port, inside the water jacket could compensate some...It would compensate some, but not nearly enough.


Frits,seeing the words outside cooling above,would it be helpful to have external water cooling on the first few inches of exhaust?I was thinking brass,copper or stainless tubing tightly wound or possibly welded to the header for better heat conduction.Inexpensive and simpler to figure out vs welding up the cylinder to add water passages it would seem.The first few inches? I have no idea what those are, some new unit of measure maybe? :devil2:
OK, joking apart, cooling the first part of the exhaust duct is highly commendable. It should be done over a length that can contain the cylinder capacity. Cooling further downstream will only be beneficial if the exhaust pipe is too short.
Winding tubing around any pipe won't do much good for cooling. If you must cool a pipe, welding a water jacket around it is a hundred times more effective.

[F5 Dave]

Port is now 28mm, so there is room. Don't have extra rings to test. Piston is Italian GPM, and appears much more decent quality than the typical far east choices. Rings do not have a coating and look decent, but are magnetic.

It's an AM6 cylinder with Suzuki piston. Stock the transfer timing is at 130deg and blowdown will not be staggering even with raised exhaust. Will see how it all pans out after we get it on the case, but expect to machine the lower end of the cylinder as the piston is little shorter than stock.

The aggregate angle of the piston with the flat at the edge is ~15% and the 44mm is 4mm overbore with 39mm stroke. So the angles may be reasonably close after all. Basic trigonometry says 2mm per side you'd use 3 deg less angle for the new bore with original type piston.
I appreciate the oversquare by boring out is not ideal with the implications to transfers. Two wrongs usually do not equal one right, but in this case higher dome and overbore impact to transfer angles may actually fit somewhat together. I'm however building a angled porting tool to adjust the transfers.



I wholeheartedly agree. I would have liked to use another piston which has much shorter compression height and 10mm longer rod, but it's out of the question because of the budget constraints. Without going into lengthy personal history, I can dedicate much more time than before and very little funding to my kids at the moment. Used to be vice versa. Life has it's surprises and the bad ones may be good ones as well. My 15yr son paid for the bike out of his own pocket and got much better one than he expected, because we could buy one previous owner didn't know how to fix and we did it together.

I have a lot of experience in the 4-strokes, decent tools and even a crude flowbench which can be used to test basic wet flow, but 2-strokes are a learning curve.
Yer making me cry, but only for those poor sweet lost horseypowers. On my Suzuki having finally changed to KX60 43mm piston, after years of dreadful Suzuki pistons, and having to destroke to do so it was still a big improvement. . . and they come in 1mm oversizes.
Skim the base if you can't afford the longer rod ATM.

[Jannem]

Yer making me cry, but only for those poor sweet lost horseypowers. On my Suzuki having finally changed to KX60 43mm piston, after years of dreadful Suzuki pistons, and having to destroke to do so it was still a big improvement. . . and they come in 1mm oversizes.
Skim the base if you can't afford the longer rod ATM.

No need to cry for the HP that never was there to begin with. :D

Skimming the base is in the plan. Gotta see where all the timings exactly fall first.

Curious how much you gained from the long rod, short piston route?

[F5 Dave]

Thats the thing. They were there. They just escaped through poor ring control. Just jumped out of shower thinking better warn you, Std Kawi rings eat iron bore. Wiseco should be fine.

TZR rodkit allowed 13000 rpm peak with rev on, whereas suzuki parts were already at (past) limit at 12, so not one change at a time.

[136kg136ps]

Thanks for the humor and reply Frits.

[Jannem]

Std Kawi rings eat iron bore. Wiseco should be fine.

TZR rodkit allowed 13000 rpm peak with rev on, whereas suzuki parts were already at (past) limit at 12, so not one change at a time.

Is that bore eating because of the differences between rings meant for nikasil vs. iron bore? I'm unfamiliar with coated bores...

Wouldn't destroking impact the timings as well? How much did you destroke? Did you increase the bore at the same time?

[F5 Dave]

Yeah they had soft rings which on placed bore was no problem, but soft on soft is like rubbing two blocks of cheese together. I plated the bore and sidestepped the issue. Most rings can handle either.

I had to destroke quite a bit to get back into class limits 53cc max, something like 37.6. Started with a new barrel. As we've learned here not an ideal configuration.
But even with that disadvantage the better components win out.

[Jannem]

Yeah they had soft rings which on placed bore was no problem, but soft on soft is like rubbing two blocks of cheese together. I plated the bore and sidestepped the issue. Most rings can handle either.

I had to destroke quite a bit to get back into class limits 53cc max, something like 37.6. Started with a new barrel. As we've learned here not an ideal configuration.
But even with that disadvantage the better components win out.

Interesting, and new stuff coming all the time. Thought those rings were harder... 😂

I'm probably committing a forum suicide, but I was thinking about using a chainsaw piston that is fully open from sides and practically see through. This with single exhaust and opening transfer entry to the bore all the way to the cylinder base.😄

[190mech]

I looked at chainsaw pistons for a build a few years back,the skirt was too short and would open the exhaust to the crankcase at TDC and also the skirt width would allow exhaust to bleed thru the sides also..Found a good quality motocross piston instead!

[guyhockley]

Well - I didn't mention any names but you instantly knew my train of thought ?
Thanks for the (french) article - pity my schoolboy french is too many years ago - although I can pick up some interesting thoughts - the pork chop thing would appear to be an easy way to gain some case volume - although as Wobbly says - full circle is better - it may be possible to slim the flywheels (on the inside face) to the crank pin depth - and regain balance weight with heavy inserts - although more research needed there to understand whether it's possible to add enough weight in the space available...
I find it interesting that lots of the 125 kart engines seem to use flywheels of around 90mm diameter and 18-20mm crankpins, as does the X30 Super Shifter 175 (63.5 x 54.5 bore and stroke, from memory). Hydroplane racing motors seem to like flat disc disc wheels with a bolt on balance weight.
http://www.grmracing.com/125-parts
Scroll down to G1020 and G1028.
Wonder what the plate is made of?

[Jannem]

I looked at chainsaw pistons for a build a few years back,the skirt was too short and would open the exhaust to the crankcase at TDC and also the skirt width would allow exhaust to bleed thru the sides also..Found a good quality motocross piston instead!

Thougt about the sides, but missed TDC entirely.😬😂

[mitch meyer]

I find it interesting that lots of the 125 kart engines seem to use flywheels of around 90mm diameter and 18-20mm crankpins, as does the X30 Super Shifter 175 (63.5 x 54.5 bore and stroke, from memory). Hydroplane racing motors seem to like flat disc disc wheels with a bolt on balance weight.
http://www.grmracing.com/125-parts
Scroll down to G1020 and G1028.
Wonder what the plate is made of?

I have GRM 125, plate material is mild steel and held in place with 3 countersunk screws.

[TZ350]

page 1750 links list.


... some may find this useful. Rather than use the site search which usually fails, use Google so to search this site use an ordinary search phrase and after it add

site:www.kiwibiker.co.nz (http://www.kiwibiker.co.nz/)

for example

Frits priceless site:www.kiwibiker.co.nz (http://www.kiwibiker.co.nz/)
or
Frits pisa site:www.kiwibiker.co.nz (http://www.kiwibiker.co.nz/)

the same will work for other sites with the appropriate site address

Mick

A lot of decade pages have small collections of interesting quotes.

The pages listed below have bigger collections of interesting quotes and useful links.

https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page1700

https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page1500

https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page1000

https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page750

https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page500



Page ..... 1500.... How to search within the ESE mega-thread?

There are over 7000 images on this thread, use "Thread Tools" to view them and then click through to the original post about them.

If you are looking for 2T tuning technical information. Because this is a show and tell thread, this thread is best read backwards, ie start at the last page and read back towards the beginning that way you get to read the answer without having to wade through the confused questions.

A lot of the decade pages have collections of quotes and links to interesting things.

Page 1500 Links List.
Page 1490 Wiseco vis other pistons discussion.
Page 1480 Discussion with data maps about why Marshengs bike runs hotter in the corners.
Page 1470 Wiseco vis other pistons and their short comings.
Page 1460 Page talks about HCCI. Bike catches fire at Wanganui Cemetery RR.
Page 1450 Working with pumper carbs.
Page 1440 The insides of the Ryger is revealed on this page.
Page 1430 Pumper carb tuning talk.
Page 1420 The Frepan TZ400 built by Wobbly. Lots of links and pictures.
Page 1410 Air/Fuel ratio meter and how to use a Lambda sensor with a two stroke.
Page 1400 2:1 Pipes, and the power advantages of cutting the Ex side of the piston short.
Page 1390 EngMod2T, simulating and testing pipe designs.
Page 1380 Dyno results, testing different sized air correction jets.
Page 1370 Links to Rod/Piston kits and parts suppliers.
Page 1360 Dyno results for some F5 Bucket 50cc bikes.
Page 1350 To much talk about the Ryger so celebrating the work other people are doing in their sheds.
Page 1340 Frits on why the ring peg should be at the 6 o’clock position.
Page 1330 Peoples interesting projects.
Page 1320 Links to Rods and Pistons technical data.
Page 1310 Celebrating Kels very neat and rather quick KR125/RS project.
Page 1300 Celebrating peoples home built racing projects.
Page 1290 People doing real Bucket building stuff. Ryger uses up a lot of space from here on.
Page 1280 Links to Peewee’s, Lightbulbs, Adegnes’s and Ken Seebers racing projects.
Page 1270 Transfer Port Theory.
Page 1260 Ex and Transfer port design with pictures.
Page 1250 Links List
Page 1240 2T development Software, Port Theory, Interesting Sites
Page 1230 Compression Ratio, Ex duct shape and length, Fancy spark plugs.
Page 1220 Reed Valve Petals, Oxygen Sensors, Exhaust duct step at the pipe flange.
Page 1210 Ignition Trigger Woes, EngMod 2T and Blow-Down, Fuelling Curve.
Page 1200 Frits on power spread and the ratio of the maximum and minimum points in the power band.
Page 1190 No data, but a lot of talk about what the Ryger engine might look like.
Page 1180 Frits on 2T fuel consumption. M50 cylinder portmap and EngMod2T analysis.
Page 1170 Engine/Gearbox oils and bearings. Transfer duct shape and optimal Ex port timing.
Page 1160 Frits - Engines need large crankcase volumes, Power vis Handling.
Page 1150 Serious talk about crankcase volume.
Page 1140 Measuring the transfer duct length, Ignitec, Expansion chamber design, Trombone pipe.
Page 1130 Team GPR Edgecumbe Videos …. Cooling 2T’s …. 3xEx vis T port,
Page 1120 Crank Balancing, Ceramic Coating, Plugs, Piston Edge chamfers, RS125 pipe dimensions.
Page 1110 TeeZees progress on the EFI thing with the Beast.
Page 1100 No Data but some talk about pickups and EngMod 2T transducer position in the pipe.
Page 1090 Links about the Detonation Sensor and Temperature Data Logger.
Page 1080 No Data, the plenum is protested, Frits on Blowdown and Transfer window height.
Page 1070 Exhaust Duct shape, Kawasaki and BRC EFI dyno videos.
Page 1060 No Data but talk about Port shape and Flow in a duct on this page.
Page 1050 EngMod2T setup talk about pipes, transfer ports and the TubMax graph.
Page 1040 Basics of pipe design and how to influence where the point of maximum depression occurs.
Page 1030 Racing at Greymouth, its well worth a look to see Team GPR in action.
Page 1020 Pipe dimensions, Seattle Smittys hydroplanes. Husaburgs piston link.
Page 1010 Suspension Tuning.

Page 1000 has a lot of useful information and links. http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page1000?p=1130773139#post1130773139

On Page 500, Bucket has links to how Team ESE built their Suzuki GP125 26, 28 and 31 hp engines:- http://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page500

Starting from the beginning I have been trying to find the posts that talk about pipes and collate and edit them. There is heaps of it, mostly from Wobbly and pages 620 630 640 650 660 670 680 690 700 710 720 730 740 750 760 770 780 1040 and 1050 have un edited collections of raw material.

[TZ350]

page 1750 links list to go here:- B

331569 331568

The two basic items needed for adapting a NSR125 or 250 cylinder to the bottom end of your choice to make a go fast water cooled Bucket engine.

Class racing rules for F4 (Buckets) have water cooled two strokes at 100cc with maximum (re bore) oversize at 110cc and two strokes over 104cc are limited to a single 24mm carb or equivalent

De-stroked crank, 48mm stroke for 110cc and 44.5mm for 100cc. Other cylinders like the RGV250, RG250, Aprilia 125 are possibilities too.

Page 1680 has all the detail you might want to know. https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page1680

Scratch around and follow the links on page 1680, there is a lot of build information to be found.

Ignition generator details are on page 1681 https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner/page1681

https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1131047135#post1131047135

Other links to NSR tuning info.

http://nsr-world.com/tuning/250-tuning/engine/ (http://nsr-world.com/tuning/250-tuning/engine/)

http://thetrxproject.blogspot.co.nz/2013/05/honda-nsr-125-jc20-3d-engine-top-end.html

https://performance-engineering.co.uk/nsr-specialists/

https://performance-engineering.co.uk/tuning/2-stroke-tuning.php

A Suzuki GP100 fitted with an un-modified NSR250 cylinder is good for 28 rwhp.

[TZ350]

page 1750 links list to go here:- C

[wobbly]

There are some very knowledgeable people out there that completely disagree with Me, Frits and Jan about the Ex duct cooling principle.
Roland Holzer in his last iteration of the Modena kart engine made the duct alot shorter, saying that this allowed the pipe ( header,spigot ) to heat up faster
when exiting corners.
Franco at TM has a radical new design in CAD that completely insulates the duct from water cooling with an air gap.
I plan on completely disproving the whole hot duct idea ( or making an idiot of myself ) by very soon having a brand new TM cylinder ceramic coated inside the duct.
This coating surface will be VERY hot where in contact with the retained air/fuel charge.
Doing exactly this process on the Britten made a heap of power, and doubled the water boil time when the bike was warmed up ( as the small rad was ducted correctly
for forward motion,not sitting still ).
It will have only one of two results on the 2T - 125 , instant detonation due to overheated gas being pushed back into the cylinder, or the engine will make more power due to
more heat energy being transferred into the pipe.
Just a very small maybe - would be both effects occur simultaneously. But deto kills engines,so that trumps the other effect every time.
The dyno will not lie,as will the deto sensor on the head.
Even if I am wrong I WILL tell everyone the result,as it has caused some very heated ( pun intended ) discussion, with lots of Italian arm waving in the process.
And of course I would REALLY love to finally prove that The Great Leader was talking out his arse about a hotter duct being better - though he sort of already did that with
his Chinese funded fiasco.

Re the GRM crank with add on web plates.
This is exactly what some new R&D idiots did to the Aprilia after Jan retired - sadly for them it suddenly lost a heap of power.
In a reed engine there is a bottom limit to the case volume that sits at around 1.3 in my experience.
The RV engine loves additional volume than that,so removing the plates on the GRM reed,and using Mallory may not work if the case becomes too big.

[lodgernz]

Mikuni TM24 with horrible manifold bent in two planes, versus Keihin TA26 with straight-line entry square on to reed block.
Which will give the best performance?
Don't know until I get some dyno time, but I'm guessing the TA.
Appears to be from an MVX250 or an NS400, and was donated/loaned by F5Dave, and originally a gift from Yow Ling.
Thank you Dave and Mike.
I have to say, it's a bloody big carb for a 50, only clears the frame by 2mm. Probably the same casting they use for the 36mm carb.

[Grumph]

Did you check for dribble at steep angles ? I mocked up my pair the other day and found that even with the tracts dead vertical there seemed to be no weeping from the pilots...I'll be using mine with the top covers pretty well horizontal - so back a bit from full vertical downdraft.

[husaberg]

Mikuni TM24 with horrible manifold bent in two planes, versus Keihin TA26 with straight-line entry square on to reed block.
Which will give the best performance?
Don't know until I get some dyno time, but I'm guessing the TA.
Appears to be from an MVX250 or an NS400, and was donated/loaned by F5Dave, and originally a gift from Yow Ling.
Thank you Dave and Mike.
I have to say, it's a bloody big carb for a 50, only clears the frame by 2mm. Probably the same casting they use for the 36mm carb.

Easy to adapt to tps as well as the later models had it as std.

[WilDun]

Hi guys .I have just come across this in a motoring magazine that comes to work
Cant see it working to be quite honest

I believe it has been working for quite a while - the guy who designed it is an (ex) South African racing car driver turned Aussie. Like all these breakthroughs, even though they work, they still have to break through the wall of "status quo".

[Jannem]

I plan on completely disproving the whole hot duct idea ( or making an idiot of myself ) by very soon having a brand new TM cylinder ceramic coated inside the duct.
This coating surface will be VERY hot where in contact with the retained air/fuel charge.

Will be very interesting to hear what it did. Makes me wonder though, whether it's close enough apples to apples, because that coating is an insulator that reflects heat rather than absorbs it, and its thermal mass is very small for whatever it absorbs. So you might actually get hotter exhaust, cooler intake charge in ex duct, as well as cooler bore. Possibly.

So, I'm betting a bottle of Koskenkorva, that you'll make more power, but it's not because hot exhaust duct idea works.😊

[diesel62]

I believe it has been working for quite a while - the guy who designed it is an (ex) South African racing car driver turned Aussie. Like all these breakthroughs, even though they work, they still have to break through the wall of "status quo".
If it runs on straight petrol as the article about says. How do they lubricate the piston? The bore is sealed from the crankcase

[WilDun]

If it runs on straight petrol as the article about says. How do they lubricate the piston? The bore is sealed from the crankcase

I believe that the design allows seepage through the gland between the crankcase and cylinder, it is not totally sealed - the piston being straight line ( not having sidethrust forces ) requires minimal lubrication. (how that works I don't know, but it's not my theory, however I did read that somewhere re: this engine).
Probably, like many glands, they have multiple 'chevron'' type seals and so seal one way but allow seepage the other way.

Here is a link which says that he is a bit cagey about how the piston is lubricated, it might be as I mentioned but it might also have oil fed through small passages inside the piston to the periphery - who knows?

http://www.f1technical.net/forum/viewtopic.php?t=12589

[diesel62]

I believe that the design allows seepage through the gland between the crankcase and cylinder, it is not totally sealed - the piston being straight line ( not having sidethrust forces ) requires minimal lubrication. (how that works I don't know, but it's not my theory, however I did read that somewhere re: this engine).
Probably, like many glands, they have multiple 'chevron'' type seals and so seal one way but allow seepage the other way.

Here is a link which says that he is a bit cagey about how the piston is lubricated, it might be as I mentioned but it might also have oil fed through small passages inside the piston to the periphery - who knows?

http://www.f1technical.net/forum/viewtopic.php?t=12589
Thanks that opens a whole lot more questions ☺️

[oldjohnno]

Will be very interesting to hear what it did. Makes me wonder though, whether it's close enough apples to apples, because that coating is an insulator that reflects heat rather than absorbs it, and its thermal mass is very small for whatever it absorbs. So you might actually get hotter exhaust, cooler intake charge in ex duct, as well as cooler bore. Possibly.

So, I'm betting a bottle of Koskenkorva, that you'll make more power, but it's not because hot exhaust duct idea works.😊

Imagine it's a hot day, say 35deg outside. Out in the yard lies a steel crowbar and a wooden handled shovel; they've both been in the sun for hours so they are both around the same temperature. But you just know that the crowbar is going to heat your hands up a hell of a lot more than the wooden shovel handle which won't hurt at all. I think the coating might be like the wooden handle - very hot but with a low thermal mass and a relatively low capacity to transfer that heat.

I should also mention that any work involving a large crowbar is inadvisable regardless of the weather....

[Haufen]

There are some very knowledgeable people out there that completely disagree with Me, Frits and Jan about the Ex duct cooling principle.
Roland Holzer in his last iteration of the Modena kart engine made the duct alot shorter, saying that this allowed the pipe ( header,spigot ) to heat up faster
when exiting corners.
Franco at TM has a radical new design in CAD that completely insulates the duct from water cooling with an air gap.
I plan on completely disproving the whole hot duct idea ( or making an idiot of myself ) by very soon having a brand new TM cylinder ceramic coated inside the duct.
This coating surface will be VERY hot where in contact with the retained air/fuel charge.
Doing exactly this process on the Britten made a heap of power, and doubled the water boil time when the bike was warmed up ( as the small rad was ducted correctly
for forward motion,not sitting still ).
It will have only one of two results on the 2T - 125 , instant detonation due to overheated gas being pushed back into the cylinder, or the engine will make more power due to
more heat energy being transferred into the pipe.
Just a very small maybe - would be both effects occur simultaneously. But deto kills engines,so that trumps the other effect every time.
The dyno will not lie,as will the deto sensor on the head.
Even if I am wrong I WILL tell everyone the result,as it has caused some very heated ( pun intended ) discussion, with lots of Italian arm waving in the process.

That's an interesting question,

How are you going to test this? Under which conditions? Steady state? Dynamic? Laptimes? And which parameters of the engine do you plan to change during the comparison?

I suppose a very well cooled exhaust port transfers about 8 hp more heat into the coolant which should then raise an engine temperature of 40 deg to about 44 deg. So as a starting point, the engine with the well cooled exhaust has a disadvantage of about half a pony or so. The question is then, can you gain more than that by throwing advance and compression at it until the same level of deto is reached? Probably yes, but the engine might need a shorter pipe first. If you can also run leaner this should recover some of the exhaust heat.

Is it really desirable to have the pipe heat up as fast as possible? If the heat up characteristic matches the track and the gearing this could also give an advantage due to a wider dynamic powerband, couldn't it?

The more I think about it, the more parameters come to my mind. This seems like at least a full week of testing if planned and executed thoroughly. I am looking forward to the outcome!