ESE's works engine tuner

[ken seeber]

Fellers,
Just thought I’d get my mind clear on the Ryger features that we know of:

• 90 rod with the standard VM bore and stroke
• Same crankshaft & cylinder head
• Reed valve appears to be positioned as in pics, essentially shifting this from the standard KZ crankcase position to the cylinder in a position similar to Rotax/Aprilia cylinders
• Wet bottom end
• Ø30 carb is fed with straight fuel
• 20 mm spacer plate under cylinder
• Slightly modified (internally) cylinder, sort of implying at least the A & B ports (from the outside) and presumably C ports are utilized.
• Single exh port
• Plain piston skirt visible thru exh port
• 11 transfers passages are indicated. Assuming the standard transfers are utilized, this means another 6 passages are added
• An engine can be converted in one day, sort of indicating that, with the addition of certain key components and there wouldn’t be casting changes required
• The system can be applied to crankcase scavenged engines, reed or rotary valve, not sure about piston port. Whether this means that the existing inlet system is retained or blanked off and replaced with the cylinder reed is unclear.
• Can be applied to four stroke engines in terms of mechanical and thermodynamic aspects, but not gas dynamics

Anything missing or wrong?

Frits, any more titbits to add?

[philou]

Ryger ?

Reed valve piston

[Lightbulb]

I like the melted piston fix. Very funny indeed.


Neil

[Frits Overmars]

Yesterday I mailed Harry Ryger the link to Breezys post with the Rygerised-cartoon:
http://www.kiwibiker.co.nz/forums/sh...post1130909828
When he clicked on it he got this:

ryger, you do not have permission to access this page. This could be due to one of several reasons:
Your user account may not have sufficient privileges to access this page. Are you trying to edit someone else's post, access administrative features or some other privileged system?
If you are trying to post, the administrator may have disabled your account, or it may be awaiting activation.

Harry repeatedly reported this problem before. No wonder we do not see any reactions from him here.

As rpm goes up the actual peak load of the piston pushing down on the rod gets less and less because of piston acceleration and less yet at overrev when the engine isnt making as much torque.

As the revs go up into Ryger territory the piston isn't pushing down on the rod at all; the rod has to pull the piston down because combustion pressure alone cannot accelerate the piston fast enough.
Then after the piston has passed its max.velocity position it has to be slowed down again so now it starts pushing down on the rod - the higher the rpm, the harder it will push.

Maybe you could answer this Frits, since we're best friends now. Is the Ryger piston lighter or heavier than a RS125 piston?

Nice question my friend. Do you mean the Honda RS125 production racer or the Aprilia RS125 street bike or maybe some other brand that I don't know of yet?
Never mind; I do not have the piston weight of either bike at hand.

Fellers, Just thought I’d get my mind clear on the Ryger features that we know of:
• 90 rod with the standard VM bore and stroke
• Same crankshaft & cylinder head
• Reed valve appears to be positioned as in pics, essentially shifting this from the standard KZ crankcase position to the cylinder in a position similar to Rotax/Aprilia cylinders
• Wet bottom end
• Ø30 carb is fed with straight fuel
• 20 mm spacer plate under cylinder
• Slightly modified (internally) cylinder, sort of implying at least the A & B ports (from the outside) and presumably C ports are utilized.
• Single exh port
• Plain piston skirt visible thru exh port
• 11 transfers passages are indicated. Assuming the standard transfers are utilized, this means another 6 passages are added
• An engine can be converted in one day, sort of indicating that, with the addition of certain key components and there wouldn’t be casting changes required
• The system can be applied to crankcase scavenged engines, reed or rotary valve, not sure about piston port. Whether this means that the existing inlet system is retained or blanked off and replaced with the cylinder reed is unclear.
• Can be applied to four stroke engines in terms of mechanical and thermodynamic aspects, but not gas dynamics

12 of the 13 items you specified are correct. The one remaining item is not exactly wrong but I feel it would need some clarification. Alas, I am not yet allowed to give it.

[SwePatrick]

As the revs go up into Ryger territory the piston isn't pushing down on the rod at all; the rod has to pull the piston down because combustion pressure alone cannot accelerate the piston fast enough.
Then after the piston has passed its max.velocity position it has to be slowed down again so now it starts pushing down on the rod - the higher the rpm, the harder it will push.

That seems in my eye´s impossible.
If there is no power(pressure) on piston, how can it accelerate?
As when a twostroke has it´s fastest pistonspeed just before or after exhaust opens.
And as you stated, the cylinder doesn´t give away anything if piston is in it´s lowest position, about 195-200degree duration exhaust.
Perpeteum mobile?

[husaberg]

Yesterday I mailed Harry Ryger the link to Breezys post with the Rygerised-cartoon:
http://www.kiwibiker.co.nz/forums/sh...post1130909828
When he clicked on it he got this:Harry repeatedly reported this problem before. No wonder we do not see any reactions from him here.

.

http://www.kiwibiker.co.nz/forums/me...hp/48608-ryger

It appears his profile has been set to Made BOO BOO in Nappies I would say its a spam related misunderstanding I have reported it to Mr Trousers.

[Frits Overmars]

That seems in my eye´s impossible. If there is no power(pressure) on piston, how can it accelerate?

It can't. But you may want to reread my post. And if that doesn't help, then take a look here: http://www.pit-lane.biz/t1461p32-tec...moteurs-motogp

[Frits Overmars]

http://www.kiwibiker.co.nz/forums/me...hp/48608-ryger
It appears his profile has been set to Made BOO BOO in Nappies I would say its a spam related misunderstanding I have reported it to Ms Trousers.

Thanks Husa.

[ief]

(ryger)

Not really thought it through but here goes...

What if the piston isn't attached to the conrod at all?

[Frits Overmars]

What if the piston isn't attached to the conrod at all?

You've lost me, Ief. How about a little sketch (for the future Ryger Art Gallery)?

[jonny quest]

How long have you known about the Ryger, and it's concept Frits?

[MotleyCrue]

As the revs go up into Ryger territory the piston isn't pushing down on the rod at all; the rod has to pull the piston down because combustion pressure alone cannot accelerate the piston fast enough.
Then after the piston has passed its max.velocity position it has to be slowed down again so now it starts pushing down on the rod - the higher the rpm, the harder it will push.

Makes perfect sense. I just wasnt sure how high in the rpm it would have to be before that happened.

[ief]

You've lost me, Ief. How about a little sketch (for the future Ryger Art Gallery)?

Not exactly the reaction I was going for, maybe should have thought about it a litlle bit more, lol. Lets call it a brainfart then

Anyways, something like this, not to scale and all that.

[F5 Dave]

I had a piston arrangement just like that when the top disconnected above the gungeon pin. I can confirm that it was less than satisfactory in operation, and increased lap times significantly.

[ZdenekK]

I've been reading this thread for some time with great interest and would like to thank you for sharing all the knowledge and great ideas on two-strokes. It's very inspiring.
As most of us there I'm very curious on the Ryger engine.
Then I got to post of MotleyCrue on page 1323 with reatarding of timing and start thinking, what if...

If we shorten the piston skirt on exhaust side enough to connect crankcase with exhaust so it will open and close like piston-ported intake, then with right timing the blow-down presure erupting from opening exhaust port will enter crankcase and boost its pressure (pressure ratio of crankcase-cylinder). Good for high rpm, hot exhaust gases probably good for starting HCCI and as a bonus the engine will be still possible to start like before.
What more, if the engine rev high enough, so the returning positive wave from exhaut woud be otherwise too late to push escaping mixture back to cylinder, it will push it thru just opened "port" under the piston to crankcase. Boosting its pressure again and pushing the RPM higher.
If this works it can mean that the exhaust pipe in powerband is not pushing mixture back into cylinder anymore, but to the crankcase instead.
Relatively cold exhaust gases of HCCI in combination with requirement of late returning positive wave from pipe can explain why the exhaust pipe on the Ryger looks very common for such extreme revs.

It's crazy enough and very simple in principle, requiring not more than cutting-off piston skirt and retarding ignition.

You can replace crankcase with "volume under the piston" in my text above, because in Ryger it probably isn't crankcase.
If such idea or in that manner was already presented, just ignore my post.

Questin of mechanical reliability at 30kRPM is stil beyond me.

PS: sorry for my poor english
BTW connecting of exhaust to crankcase is nothing new, it's been done in karting for years, just not in such extreme way.

Regards
ZdenekK - Czech moped rider