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Hey guys, I just joined here and bought a 02 450R a few weeks ago and have been loving it. I have read a lot on this forum and it has helped me out a bunch. I am a mechanic by trade so working on these is actually simple and refreshing. I went through and did the full service, checked valves and all that good stuff. The other night I was riding a wheelie in third and my foot accidentally bumped it into fourth. When that happened the trans made a audible bang and it shifted funny. When I stopped and shut the bike off I could not get it in neatraul. I noticed the countershaft sprocket bolt had come loose. I somehow managed to get bike back to neatraul. It shifted through all gears but had a weird notchy feeling at the end of the shift. Any clues what happened and if I am on borrowed time this season? I don't really want to strip the motor down right now, but I don't want to grenade it either if something lets loose. Thanks for any help guys.

the only thing I can really think of that might have happened is a bent shift fork, even the slightest flex in it can screw up the movement in the shift drum. or you might have messed up the valley in the shift drum.(very rare for that one) or possibly just have messed up splines in your shift lever, and the teeth are just sloppy. check it out and keep me posted.

I will do a little investigation here shortly. I guess I will yank the clutch basket and take a peak.

you wouldn't really know until the cases have been split. there are lots of parts in there, I would suggest having the manual for the bike.

I was assuming that the shift lever shaft comes through to the clutch side of the case to actuate the shift drum? Just thought I would check there first and make sure nothing was bent there. I really dont want to split the cases until winter if I can help it.

Well just an update guys. I got the engine out of the bike and got it mostly tore apart. I need to find a socket for the balancer shaft bolt and a flywheel puller. When I pulled the shifter shaft out, it felt like something dropped even though nothing else rides on that shaft. So I looked through the holes and it appears to be the tip of a shift fork. My questions are, where can I find one of those 4 sided sockets with the notches? Also, while I am in here, other than repacing the damaged transmission pieces and all gaskets is there anything else I should just replace or inspect closely? The crank and top end were just done within 8 or 10 hours and looks brand new. I just dont want to pull this apart for anything else. Thanks for the help guys.