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Crf250r piston and cam marks, did I catch it just in time ?

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Hi everyone I am rebuilding the top end on my mates 250r and I noticed the cam , bucket and shim are marked like they have been hot or so, I'm assuming this isn't normal but is the cam now wrecked? It still feels smooth but I'm not sure, also I might replace the bucket as I have a spare parts motor , he was told the piston is a custom $350 piston imported from the U.S is this true? There is no brand name on the piston or is it a Honda piston and am I lucky I stripped it in time judging by the valve indents on the piston, all your help will be greatly appreciated thanks ImageUploadedByThumper Talk1453375724.734646.jpgImageUploadedByThumper Talk1453375744.708967.jpgImageUploadedByThumper Talk1453375760.350315.jpgImageUploadedByThumper Talk1453375777.160088.jpgImageUploadedByThumper Talk1453375796.068849.jpgImageUploadedByThumper Talk1453375810.525648.jpg

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The cam and bucket should be replaced because the RS intake cam lobe is damaged, probably because the RS intake valve lost all its clearance (at some point wore out and wasnt repaired soon enough) resulting in constant contact between that cam lobe and bucket. Also can see the exh valves were making contact with the top of the piston and it looks like a wiseco piston. The valve timing must have gotten out of sync at some point also, possibly has a bad chain tensioner.

Could have been worse but checking the valve clearance and making the necessary repairs would have saved some $

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I have a 2005 Honda crf250 that is almost impossible to kick start I baught the bike it had problems kicking I braught it in where I baught it they said they adjusted the valves it started kicking again a week later it stopped but bump started first time everytime and kicked once hot .. I bring it to a guy we have it torn apart we are seeing my Valve is running my cam down and that my intake valve is too tight we are thinking this is the problem for it not kicking does anyone know how to solve this problem without buying a whole new head or how this even happend ??

I have a 2005 Honda crf250 that is almost impossible to kick start I baught the bike it had problems kicking I braught it in where I baught it they said they adjusted the valves it started kicking again a week later it stopped but bump started first time everytime and kicked once hot .. I bring it to a guy we have it torn apart we are seeing my Valve is running my cam down and that my intake valve is too tight we are thinking this is the problem for it not kicking does anyone know how to solve this problem without buying a whole new head or how this even happend ??

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When running a hi comp and a cam u should always check piston to valve clearance.

That motor was about to lunch big time

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Yeah I told my mate he was very lucky it didn't grenade, the head is getting sent to Serco for new valves and full recondition/check over so it'll be good, I have a good stock cam and buckets off a spare motor I have so I'll use them in it , new piston to stock specs will be used aswell , cheers

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After piston to valve contact a new crank would be required. Even if it feels ok, the big end bearing would of taken a hammering and continuing to run it will end in disaster. Probably sooner rather than later.

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