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Valves touching piston!? Now with pictures

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Hopefully this is my dreaded tick/knock/noise i don't want to ever hear again. Finally broke down and brought my 08' 250f to a KTM dealer and got their advice. I thought the slight ring from intake valves on the piston was normal, but it appears not (first four stroke tear down). Timing was set correctly(TDC lock + cam tick marks) and the new dirt tricks cam chain tensioner was set correctly.

Valves were checked tear down and all within spec, and the head (with valves) was checked for leaks, but all valves were fine. So it appears that somehow the intake valves are off timed somehow.

Per mechanic advice my new parts list is now: New cams, new piston/rings, and new cam chain. Any other advice on the timing issue, and if the cams are replaced should I replace every part of them (cam gear and bearings) or can any part be reused?

No major visible signs of wear/heat except for slight heat on the gear of intake cam, any comments?

And of course, pictures:

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wow, I would insist the true cause be found before it runs again, ie cams compared

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Still have a bunch of questions, if possible:

Any advice or thoughts on why only the intake pistons were hitting? I'm still scratching my head on what could of caused it. Luckily it didn't seize or blow up, but just very curious at this point. Valve clearances were dead on before I tore down the motor and even with the new manual cam chain tensioner the knock was still there. The old cam chain tensioner was acting funny when I took it out, so maybe it messed up the cam chain, but wouldn't that affect both cams?

If I replace both cams can any part of the old one's be salvaged (bearing or gear)? Everything looks fine except for that heat mark on the intake cam gear. Or should only the intake cam be replaced?

Also, what's the recommended piston kit? I was told ProX, but haven't done much research past that.

Sorry for all the questions, but I really appreciate the help of these forums.

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Why do the cams need to be replaced? They look to be in pretty decent shape. That looks like an original or OEM piston. Has it been rebuilt before? Something is out of spec.

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check your crank there was a bulletien about some substandard cranks on the 2008's

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Have you had the bike since new, the head could have been skimmed at some point to increase compression, have you checked the Conrod it could have streatched over time, I'd feel these are more likely to be the culprit rather an actual cam being off

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your lucky, bought mine used and didnt really notice any noise for a while, then did a tear down because i thought the main bearings were goiing...211 hrs, and found the same thing as in your bike but worse....the noise that i thought was the main bearings happend to be where the crank web had cracked and was grinding against the con rod witch had nearly welded its self together.....good thing for full syn engine oil or it could have been worse. my guy only charged me 500$ labor and total for all was 1800@ piston,rings, valves, seals keepers, crank, main bearings, and all gaskets....and this all was because the last guy in the motor ( who owns a shop ) had the intake timing off by one tooth!!!

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no typo....bought off a mutual friend who is a pretty advanced racer, and has his own mx shop.....told me it was on its 3rd top end 2hrs ago and has never had to adjust a valve!! other than piston maintainance, only wear items were replaced, clutch, tires....and so on. I got it with 187 on the clock...and it didnt really make an strange noise till 211.3. so......i think a lesser bike would have granaded with the valves hitting the piston for almost 20 hours...but its a ktm and it held together long enough to get some attention.....good, bad or indiffernt....its the bike i have now. and with alll the other little stuff i have done....its paracticaly new!!!

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check your crank there was a bulletien about some substandard cranks on the 2008's

Yeah, called just to be sure and no bulletin info on my vin.

I bought the bike knowing it had a knock, so I'm not devastated with the problem. The guy I bought it from got burned because he didn't notice the noise, and I bought it thinking it was just the crank.... I just wanted to fix it and flip it, but I'll be lucky to break even now. I'm going to replace cam chain and case bearings to at least get the case together for now then look at cams again when I recheck timing. I know they look fine to me but something on the intake side is off for sure. Is it possible that the cam chain messed up the intake cam gear and turned it off time? The cam chain tensioner was definitely acting funny when I took it out.

Valves were in spec (within a thousandth of each other, .006 I think).

Any recommendations for piston kit? I was leaning towards ProX as I was recommended, for ~$180 off ebay, but OEM is only $236. Not really looking for for performance at this stage.

Thanks again for the help

edit: Judging from the frame wear and tires, the bike probably had about 10-15 hours on it. That's why the motor acting so funny is pretty confusing for me too.

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