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05 crf 450 okay to ride??

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okay so ive got an 05 crf 450 and i just picked it up a few weeks ago and im really happy with it but i have an issue. I took it to a mechanic just to get the valves checked and a leakdown test performed just to be safe. The valves were all in spec and hadnt even moved out of adjustment which is great but the leakdown shows an 18% blow by past the piston rings which means i need new rings, piston, etc... He also said im going to want a new cam chain. im planning on doing that of course but im supposed to go ride samoa dunes for labor day weekend and ive had the trip planned forever. The mechanic said it will probly be fine to ride it one more time but i want your guys opinions on what to do based on experiences with this kind of stuff. The bike starts first or second kick, idles fine and i wouldnt of even known anything was wrong exept for the leakdown. PLEASE i need your help! thanks

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Honestly, if it starts on the first or second kick, I'd run it. When it gets real hard to start, look into a new top end. BTW, I don't think you'll be doing any harm in running your bike over Labor day weekend.

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if you do your research on the motors, at about 10 hours the crf450 loses about 4-5 hp due to the piston and single ring design. So your 18% is about what I would expect. Many people ride them 100 hours before changing the piston. you would gain a bit of HP by installing a new piston and rings, but only a few can actually ride a bike with 45hp let alone 50+ to its full potential. And they are all Pros or retired pros.

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When it stops running or starting easy than do the top end. But I would go have fun. If you are doing to do a top end you might as well get your use out of it. Do it after.

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if you do your research on the motors, at about 10 hours the crf450 loses about 4-5 hp due to the piston and single ring design.

I love this place. How did we find out about things like this before the internet?

If you go ahead and go through the trouble of replacing the piston, are there after market parts that don't have the same early power loss issue?

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