Other Help with R&D cylinder

[Nemo]

Does anyone have the story on these R&D cylinders and head? Any info would be great. Thanks in advance.

 

[mxmark4]

I have orings for that head. That's all I can tell you

 

[Pablo]

Contact Paul Lehr.

 

[GIL]

Is that not a DASA for R&D cylinder setup?

 

[waxhead]

Thats an early dasa cylinder, Set up right it will make your ski fly.

 

[customride0105]

I had this same set up as a 5mm stroker 752cc(stock bore) and was flipping my freak. Tj did the port work. I forget who bought it but I believe he's pleased also..

 

[loictahiti]

It's blingblingless , but works fine if the port job is done by specialist .
We have one here, 85 mm + 5 stroker, ported by Art, it's ripping all the time .

 

[Big Kahuna]

holy crap that is clean!

 

[ADDict]

I run this cylinder in an 8mm setup with 82mm bores (802cc) and it rips for its size! I was flipping a heavy glass Rok hull with it. Great power at somewhat of a budget cost by comparison. Tricky1 built mine.

Sent from my DROID RAZR using Tapatalk 2

 

[tipafew]

I had this same set up as a 5mm stroker 752cc(stock bore) and was flipping my freak. Tj did the port work. I forget who bought it but I believe he's pleased also..

I bought it......And yes.....it is a beast!!!!!!
Great cylinder. It smokes some much bigger displacement motors.

That thing is mint!!!

 

[Nemo]

This cylinder measures 131mm from top of cylinder to bottom of cylinder (not bottom of sleeve). Exhaust port looks like 40mm from top of cylinder.

 

[Knoxie]

131mm cylinder height would probably equate to a 8mm stroker crank running long rods (133mm kawi rods) , with normal yamaha dome pistons (as opposed to kawi flat tops)...port timing calculator with those specs gives exhaust opening timing around 85deg

 

[Nuklear6]

131mm cylinder height would probably equate to a 8mm stroker crank running long rods (133mm kawi rods) , with normal yamaha dome pistons (as opposed to kawi flat tops)...port timing calculator with those specs gives exhaust opening timing around 85deg

You beat me to it. My calculations put it just under 85 deg atdc. Not the best freestyle engine with the exhaust port cut as high as that one is. Was prob built for a racer.

 

[Nuklear6]

I should add that with that port timing if you run big compression, race gas, and total loss you could prob get it to hit pretty damn good on the bottom. And for everyone in the world that would rather talk duration instead of opening (Zack and Trevor). Exhaust duration for above setup would be 190.6 degrees

 

[Nemo]

Thank you for the information guys.

 

[jetpilot36]

wanna sell it?

 

[DangerBoy]

since the transfers look untouched ,there dosnt appear to be much squish cut in the head ,and it has tall mounting bosses my GUESS is thats a standard 3rd gen Lamey cylinder, set up for a 6mm stroker crank with long (133) rods
still have a similar set up in my FX-1, super dependable tons, of power
Db

 

[Nuklear6]

Db Is correct. I did not look at the picture of the head last night. There is no squish relief cut in the head therefore tdc would have to be at least -.045 deck height. The above calculations are for 0 deck height. However with a +6mm/133mm rods and .045" deck height your still under 85 degrees atdc exhaust opening. Which like said above isnt the best for off idle power with out some compression and goodies...

Best thing you could do is ditch the head (use a head with removable domes so squish relief can be cut in the head), and machine cylinder to be 0 deck height with a +4mm stock length rod. Could get pretty close to 89 degrees atdc. Now thats getting close to being really good for off idle power with pump gass compression. BUT of course its less displacement....