I’m looking for a high compression 100mm 02-08 CRF450R piston for my 05 motor. Highest I can find is the CP M2052 which is 13.5. Anybody familiar with a piston that’s higher than that? Thanks!
Ha! No worries. Head is decked but combustion chamber has some work done to it and I want to make up for the difference in combustion chamber size. Was running a 14.25 Venom, but obviously those aren’t available any more lol. Trying to not deck the head anymore and mess up the timing if at all possible.
Have you spoke with John @ Racers Edge? They build some high compression motors. I spoke with him not too long ago. He was mentioning overall 15:1 Some of that may come from their head. Good luck with the search.
I’ve talked with him. He’s scared to death of compression. I told him I’m at 13.4:1 on my 501 and he thought that was insane, and said he’d never ship a motor that was run all day long with that kind of compression. Which is funny because I run pump gas. . . .
Odd. That is not what he told me. He was very clear on a all bore, high compression motor. I even told him my type of riding, wide open farm fields and trails. Maybe he was talking strictly drag racing.
Zero need for over 13.5 static compression, and I'm guessing you'll have even more since it's sounding like you're trying to run a '04/05 stroker crank that's been bushed down to a 19 pin so it keeps the 111 rod. All they do is fight the over-rev when you stack a TRX full of compression, hence the need for a Dyna, especially on low octane fuels.
The 2052 and 2054 are actually really good pistons with clean dome designs. Remember it isn't always about big compression. You can make over 70 with 13:1 shelf CP pistons in almost every combo available.
Thanks for the reply Morgan. The reason I’m looking for the hi compression piston is just to get me back to my desired CR, because, as you know, the first gen head has much more volume, and after unshrousing the valves and chamber for a bigger bore, that volume only increases. Again, I know you know these things, but just spelling it out for anybody else reading. I’d have to look at my build notes, but even with a 14.25:1 piston I believe I was just over 13:1 static, and that’s with .030 off the head. I do like the idea of a shelf piston that’s easy to find though. I dunno, I have a 103mm 14:1 BB that I should just throw on there, but I just don’t know how reliable a 575cc motor will be.
Then I suggest getting a 13:1 piston and run good pump gas. A CP M2055 piston kit would be a great 97mm piston for you.
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