ESE's works engine tuner

[peewee]

[FONT=arial]That would be quite instructive, even though the FPE is based on the 'regular' RSA engine.

theres been a few pics of the rsa cylinder exit and manifold. how do i know if its a regular cylinder or not ?

[husaberg]

There is no I in TEAM. Now it's called team work.

Aye I only have a few personalities..........
I bet you a virtual beer it has a piston.

[Frits Overmars]

theres been a few pics of the rsa cylinder exit and manifold. how do i know if its a regular cylinder or not ?

Finally a question that I can answer without worrying about non-disclosures. And it's a simple question as well; thank you peewee.
Easy answer: if it's on a photo it's regular; there are no published pictures of the experimental stuff I was talking about.

[Frits Overmars]

I bet you a virtual beer it has a piston.

You've got a lot of virtual nerve Husa. Remember this? http://www.kiwibiker.co.nz/forums/sh...post1130869024

[husaberg]

You've got a lot of nerve Husa. Remember this? http://www.kiwibiker.co.nz/forums/sh...post1130869024

Yeah but can you confirm that it is a Piston.............

[Haufen]

I don't know if this has been asked before - does the ryger engine use the stock pipe?

Okay, I think we might have a hit here (or I just missed something).

[adegnes]

I've modeled my engine with the iame m50 cylinder and my hackjob pipe as accurate as I can in engmod.
My crank is 39.1mm stroke, vs the iame 39.4mm, I've fixed this by taking 0.5mm off the top of the cylinder, 0.2mm extra for more transfer duration.
I've also further raised the main exhaust 0.9mm and the aux 1.4mm

Ignition timing is set to keep tumax below 960, but not optimized at all.
The pipe is something for a scooter with a homemade header and tailpipe+restrictor.

Here's the numbers and result:










Is this realistic?

i know there's lots more that can be done, but I wanted to start out with something I could easily do in real life with minimum chance of screwing up...

[JanBros]

was wondering about the ryger, and I don't thinck it's possible the piston/round conrod is a fixed unit with it only moving up and down through a seal in the spacer under the cylinder.
the spacer isn't thick enough. I seriously doubt it's thick enough to compensate for the skirts (?) sticking out at the underside of the barrel, so no space to fit in the seal + guide. As the piston would only move up and down it's skirts could be made shorter as they wouldn't be as nescesary to guide the piston, but than the exhaust port might be uncovered in TDC.

[Flettner]

was wondering about the ryger, and I don't thinck it's possible the piston/round conrod is a fixed unit with it only moving up and down through a seal in the spacer under the cylinder.
the spacer isn't thick enough. I seriously doubt it's thick enough to compensate for the skirts (?) sticking out at the underside of the barrel, so no space to fit in the seal + guide. As the piston would only move up and down it's skirts could be made shorter as they wouldn't be as nescesary to guide the piston, but than the exhaust port might be uncovered in BDC.

Just because the spacer looks 20mm thick on the outside doesn't mean the guide isn't taller inside, the spacer could have been machined from something much thicker or the guide ( being longer ) isn't pressed or screwed into this plate. The spacer could well fit right up to the underside of the piston at BDC.

[JanBros]

forgot to mention : if the Ryger uses 98% parts of a conventional 2-stroke engine, a different piston/crank/conrod/... + rockers/links... wouldn't fit inside the 98%

[Frits Overmars]

forgot to mention : if the Ryger uses 98% parts of a conventional 2-stroke engine, a different piston/crank/conrod/... + rockers/links... wouldn't fit inside the 98%

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

[wobbly]

Yep, there appears to be nothing outrageous in the IAME sim at all.
The bmep is reasonable, there is good superposition at peak power along with good depression around bdc, and importantly the
tuned length is on the money as the peak stuffing pressure is well before the piston closes the port.
To reduce the crank power a bit drop the combustion efficiency.
With a cleverer pipe and a proper restrictor at the header and stinger entry it would make better power everywhere - but a good start.

[adegnes]

Yep, there appears to be nothing outrageous in the IAME sim at all.
The bmep is reasonable, there is good superposition at peak power along with good depression around bdc, and importantly the
tuned length is on the money as the peak stuffing pressure is well before the piston closes the port.
To reduce the crank power a bit drop the combustion efficiency.
With a cleverer pipe and a proper restrictor at the header and stinger entry it would make better power everywhere - but a good start.

Great! Thanks!
I'll start working on that cleverer pipe!

[Flettner]

Don't tell me it's as simple as a hose clip clamped around the con rod holding a rubber boot that is also anchored to the alloy plate in the crank case? There we have it

[m4r]

regarding to that Ryger Engine, what about asymetric transfer timing, or at least one extra port above the normal tranfers, with round about the same height as the exhaust port. This extra port you would be able to only open on the compression stroke? It should catch the returning wave from the pipe below resonance rpm instead of reflecting it on the cylinder walls after normal transfers would be closed and wasting it out through the exhaust again. Also this would charge your intake volume, and you would have more pressure next time transfers open. Maybe because of that you could even lower the standard transfers and get more Blowdown TA for higher rpm.