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How often do you change your pistons?

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i was just wondering how often i should change my pistons? So how often do you guys change your pistons? what year is your 250? And last what kind of pistons?

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Really depends how fast you are and how hard you are on bikes. I re ring my piston every 10 hours, and at 20 hours i put piston, rings, wristpin etc. The piston is always good and looks great. I like stock honda stuff personally. I think forged pistons are stronger (wiseco) but they need a proper break in and also you have to be diligent to warm your bike up correctly before going out or else you can cold seize it due to the grain structure of the 2 being different. Thats how forged pistons fail mostly. I just get honda stuff cheap and like to tear down my bikes to really inspect them. Ive used forged in the past with good results. 2011 crf250 Being a single ring high rpm piston they do wear out quick. I notice a small performance increase every time i do it. I know the canadian national pro teams re ring there bikes ever race( so practice, and 2 motos probly adding upto like 1.5 hours tops. And a full rebuild every other weekend, so 3.5 hours. pretty intense!!

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I re ring every 20 hours.New piston every 40 hours.I have ran this combo with aftermarket and o.e. pistons.

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I went 87 hours on my piston on my 2007. The mechanic said I could have proably gone another 10 before it needed replaced. How ever I dont think I ever hit the rev limiter in those 87 hours. I now have 44 hours on the other piston and it is running great.

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my 09 has never been apart, still all original, even the valves have never needed shimmed. going into my 4th season, regular oil changes with Maxima oils and clean air filters. my clutch is still original too.

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really depends what kind of riding you do. When I was racing id do it every 40 hours or so. If im just dicking around like I do now ill go 75-80 hours on a piston.

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Every 20-30 hrs for hi-level competition depending on how it feels. 50-80 hrs for woods riding depending on how hard you ride it. You should know the feeling of your bike when it starts to lose power. I can tell primarily when the bike is lagging because of the holeshot my kid is getting. Since I know his riding style and how he usually comes off the line, tells me a lot. Same with bigger jumps out of the corners. When he comes up short on a jump that he normally clears easily time and time again, it's usually the bike lacking power.

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Typicaly the A, B and C pistons are like .01-.005mm difference in size. Like 77.95, 77.96 and 77.97 for A, B, C. It allows a better match to the specific cylinder. I did not think the OEM Honda had A, B and C designations, there is only one part number. I do recall when one of my sons was on KX 85's the pistons were marked A, B and C but there was no seperate part number for the different pistons. You had to look in the box and there appeared to be no reason why they didn't offer part numbers so you could select the proper piston.

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Thank You. I'll run what they give me.

My guess is they are ordering a Prox piston or possibly an Athena, they both offer A, B and C pistons.

I would go with either the Wiesco RC or the CP CPKX piston, I think they are far superior to the ProX or Athena. We have a big bore with the Athena 82mm piston but would use the RC or CP if they had a piston for that application.

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Id say 40-50 hours thats what i did on my piston and it was still in good shape. some people have gone longer but i dont like to stretch it. Not to hijack the thread but what are peoples opinions on re-ringing? My dad says theres no point to replace the rings in between piston changes, just to replace it all at once every 50 hours or so. But i have read alot of posts about people that replace just the rings between piston changes.

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Id say 40-50 hours thats what i did on my piston and it was still in good shape. some people have gone longer but i dont like to stretch it. Not to hijack the thread but what are peoples opinions on re-ringing? My dad says theres no point to replace the rings in between piston changes, just to replace it all at once every 50 hours or so. But i have read alot of posts about people that replace just the rings between piston changes.

I ran the same rings and piston for 87 hours. I would have replaced the rings half way but I dont know how. To replace the rings would have cost $150 in labor and $30 for the rings. So I just wait untill the piston needs replaced and do it all then.

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