03 WR450 Transmission failure

After many rides (about 13000 miles) - my transmission locked up today :thumbsup: (luckly I wasn't in the middle of nowhere, and there were two riding buddies with me). No problems utill now. Shifted perfectly every time.

Now I can't shift anymore - the lever is stuck, the engine still works, but when I release the clutch the engine just dies. Probably something is stuck in the transmission, any ideas ? I'm probably going open the the engine tommorow.

Opened the engine today, first the drive gear on the crankshaft was a little loose (probably for a long time) the result is displayed on this picture:


Is the crank shaft still usable ?

Next the disaster:



Have to replace 4 gears + shift fork

And the left and right case:




I was thinking to measure everything, mill seats in the cases and make two bushings to fit in the seats. Then weld everything together and then mill the shift fork journals again. Anyone done something like that ?

YAMAHA :thumbsup::thumbsup::bonk:

13k miles on a competition based dirtbike is purty good,unless it was all hgwy miles. 10k in the dirt is like 100k on the road :thumbsup:

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