Middle drive

[jrplumber1]

What causes the mid drive to leak where the shims are? Between the round plate and the place the rubber boot mounts on to and the main case for the middle drive.
And what is a good way to get this to stop?

[bikerphil]

If it is leaking where the thin shims are, the O ring around the yoke housing is probably shot. You'll have to take the 3 Allen bolts out (6MM hex), pull the yoke housing out to get at the O ring. You don't have to remove the yoke nut to do this. There is a seal behind the yoke that can also leak. Pay attention to the "up" arrow when reassembling. HTH

[jrplumber1]

I think I found the leak.

It is coming from behind the flange that the u-joint mounts to.
Is it possible to change the seal without pulling the mid drive?
And if so is there any way that it could mess up the lash on the gears by just pulling the flange and putting in a new seal?

[bikerphil]

Yeah, you can change it in the bike if you take the swingarm off. The mid drive will come out fairly easily if you want to do it that way. Just tighten that yoke nut to the proper torque after changing your seal and you should have no problems.