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Hey guys. I have a 2014 crf250. I need more power. The bikes a turd. I looked at the dyno sheet from hot cams for there stage 2 cam. Doesnt look that inpressive. Bikes got enough power down low for me but needs a lot more in the mid and top. What cam do you guys think i should use? Any advise would be helpful. Thanks

 

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IMO, one of the most overlooked performance parts in a used motocross bike is the piston.  Your thinking 'what is this moron talking about' I just put a new one in two months ago.  If you put an standard sized piston in a Jap bike over say a year old, it is probably loose enough it will run maybe ok for a couple rides then go back to being just as gutless as it was before you replaced it.  Four strokes need very tight piston clearances because the skirt is so short.  Two-three thousandths clearance may be acceptable in a two stroke but not a four stroke.  The simple and inexpensive fix is to use an incremental oversize piston - the ones with the A, B, C, or D sizing.  ProX sells them and I believe there is another company that does also.  I highly recommend a 'C' size (a little over 1 thousandth inch).  Hey, I am all for buying cams, pipes etc. but unless your motor is in tip-top shape it is like putting lipstick on a pig.

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IMO, one of the most overlooked performance parts in a used motocross bike is the piston.  Your thinking 'what is this moron talking about' I just put a new one in two months ago.  If you put an standard sized piston in a Jap bike over say a year old, it is probably loose enough it will run maybe ok for a couple rides then go back to being just as gutless as it was before you replaced it.  Four strokes need very tight piston clearances because the skirt is so short.  Two-three thousandths clearance may be acceptable in a two stroke but not a four stroke.  The simple and inexpensive fix is to use an incremental oversize piston - the ones with the A, B, C, or D sizing.  ProX sells them and I believe there is another company that does also.  I highly recommend a 'C' size (a little over 1 thousandth inch).  Hey, I am all for buying cams, pipes etc. but unless your motor is in tip-top shape it is like putting lipstick on a pig.

I was going to do a top end after this season with a standard size piston. Bike got about 70 hours on it

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