oil leaking from front sprocket countershaft

after a big impact it appears that the chain has bent the front sprocket countershaft anyone know about what kind of a job im looking at to get me out of this predicament and if this has happened to anyone else?



Edited by Braydennm

What was the impact ?

If the shaft is bent. It is a full tear down to replace it.

I recently had to replace the counter shaft bearing at the sprocket. Full tear down to replace it.

Yep full tear down to get at the inner works. If it has enough hours, it is worth your time to do a full bottom end rebuild. And replace shift forks as good practice and any bearings or seals. If you feel mechanically inclined to do so.

Are you sure the shaft is bent?


To bend the countershaft would take some massive force. The transmission cases would be busted.

A buddy of mine bent the countershaft on his 12 crf250 after running a too tight chain. Cases were fine though.

He ran it like that for several months without leaks, and then replaced the countershaft while replacing the crank.

The front sprocket wobbled all over the place, i would never dare run a bike like that.

Thanks guys, we finally got to the bottom of it, the chain would have broken before the shaft bent so we pretty much ruled that out. the impact was from jumping a new road that was cut into the side of a hill on our property and didn't quite have enough lift off the "upramp" what happened was a bit of dirt wedged its way behind the sprocket and got ground into the oil seal. A new seal is on its way. A good outcome from a bad situation I guess. Thanks again for you're help I really appreciate it.

you need 3 pieces to solve that leak :  seal, new collar and Oring

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