Countershaft leak

There's a slight leak at my c/s sprocket. Have any of you replaced the seal/o-ring there?

Is it pretty straight forward? Thx

I just replaced mine.. Pretty easy..

Get a new spring washer, o-ring, and bolt as well as the c/s seal.

You should be able to pull the old seal by removing the bushing w/ pliers and then prying the seal out. I removed mine by drilling holes in it and then threading in some screws and pulling it out, but afterwards realized it would have been easier to just do it the other way.

im actually waiting for the parts for this fix right now.... warm the bike up before you take the old c/s off, mine was real tight, i kept my foot on the brake and slowly removed bolt... i just bought bike used with a 13 tooth PB leaky sprocket.. i needed a new collar/spacer as well cause mine was scored up from sand...:worthy:

as for the seal i have a question, is it neccessary to take the whole bushing out or should you leave it in and just pull the seal out???? what do guys use a screw driver?? thanks


I don't know if this a good thing or not I added some sealent to the washer when I put mine back together to make sure it will not leak.

try cleaning first. Remove the sprocket, pull the bushing out with pliers and use a q-tip on the inner seal lip. Then clean the bushing, maybe a new o-ring. Make sure it is a KTM factory part sprocket, new washer or re-cup the old one and re-install. Seal is almost always good and doesnt need to be replaced. If it leaks again then replace it and the o-ring. Oh yes, I use a screw driver to remove the seal, Be careful not to scratch the case.

so i got all the parts in and decided to get seal was a real pain in the ass to get out....but once out everything went smoothly....with hopefully no leaks to come!!!! thanks for everyones input.... without thumper would be lost!!!! :D:worthy:

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