HELP!! scraping when you kick it

i have a 2004 yz250f and about 5 weeks ago while i was riding all the sudden the bike starts making this knocking sound (kinda sounded like piston slap). I shut it off right away and kicked it slowly and felt something scraping when i kicked it. well i decided to put in a new top end (piston, cam chain) while i had the top end off i inspected the rod and crank bearings all seamed perfect. no play and very loose. well i put it all back togeather tonight and after filling it with oil and coolent i kicked it slowly a few times and the scraping was still there:banghead: :thumbsup::moon: . I havn't started it yet im too scared to. Have any of you had this happen? what do you guys think it could be. thanks for any help!

hey, i know mine is a different bike (2001 Wr250), but something quite the same happened to mine and it sounded like top end when i was on the bike, and sounded like scraping when i turned the engine over. but it was actually my flywheel rivets, that hold it to the plate that sits on the crank. they had come loose and my flywheel rocking on the plate and scraping the geny, might be worth a look its only a few 8mm bolts to take the cover off.

hope this helps

i started it and it runs perfect. very quite. i changed the timing chain so i know the fly wheel is on right. i think it might me in the kicker itself. i just broke it in and changed the oil everything checks out.

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