R&D powervalve yamaha cylinder

[sturat]

Anyone have any experience with one?

 

[Big Kahuna]

It's just a Cast DASA / Lamey cylinder. Early AM cylinders

 

[Jr.]

I have played with a few of them in my time ( thats 10 of them in my avatar pic, ready to be ported)
PM me your questions?

P

 

[sturat]

It's just a Cast DASA / Lamey cylinder. Early AM cylinders

worth building one or just going another route?

 

[waxhead]

Yes its a good thing. Send it to JR and get it done. I have a stock stroke one in my superjet non PV and its a awesome little engine

 

[MTRHEAD]

worth building one or just going another route?

Also depends on what you want to do? If it’s an old race cylinder you need to check deck height to see if it was for a 4,5,6 or 8mm stroker. Also if it was a race cylinder could have some real high port timing and won’t work for average person without the other parts to make it violent

 

[waxhead]

Nope never heard of them

 

[waxhead]

This is my 6mm
123 and 190 port timing
Should go just nice with 48 novis lol

 

[MTRHEAD]

This is my 6mm
123 and 190 port timing
Should go just nice with 48 novis lol

That’s good timing. Mine was 202/130 8mm. Dry pipe RACE

 

[waxhead]

Yeah my one on my ski now is about that, well 198 and 128 and it rips through the mid
I have a zeeltronic on it. I was riding it this morning and this guy was saying just how punchy and throttle responsive it was.
760 44s
ported cases
v-force reeds
version 3 curve in the zeel
180 psi
b=pipe limited chamber
Stock weight flywheel

 

[Storbeck]

That’s good timing. Mine was 202/130 8mm. Dry pipe RACE

What kind of rpm did you pull with that? Seems like a hell of a lot!

 

[Storbeck]

I'm also Interested in what @waxhead is running for rpm with the super high timing and b pipe. What pitch impeller?

 

[waxhead]

7300, prop no idea its a polartis pump with the lowest putch of the props i had lol

 

[MTRHEAD]

What kind of rpm did you pull with that? Seems like a hell of a lot!

Typical race motor. 7700. Give or take 40. Type 9 dry pipe

 

[waxhead]

Typical race motor. 7700. Give or take 40. Type 9 dry pipe

Type9 will do that

 

[Storbeck]

Thanks guys that's interesting, surprising to me that much timing and still not all that high rpm.

Sorry for distracting your thread sturat.

 

[MTRHEAD]

Thanks guys that's interesting, surprising to me that much timing and still not all that high rpm.

Sorry for distracting your thread sturat.

95% of every pro level boat was 198. Most 7500-7800 rpm

 

[waxhead]

Thanks guys that's interesting, surprising to me that much timing and still not all that high rpm.

Sorry for distracting your thread sturat.

Its a limited b-pipe so thats probally knocking down the top end and giving it the punch.
but boy does it have some punch in it.

 

[Vortex]

Rode one a few times that does 62mph, and it was a handful! A lot more nimble than a 1100sxr

 

[Eric sears]

Also depends on what you want to do? If it’s an old race cylinder you need to check deck height to see if it was for a 4,5,6 or 8mm stroker. Also if it was a race cylinder could have some real high port timing and won’t work for average person without the other parts to make it violent

I recently purchased a non pv cast r&d cylinder, how can I measure the stoke and port timing?