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Where do I start??? K75S, 1986

dieselyoda

Active member
Huh?
leakone.jpg

Puddle of oil, gear oil, on the floor, some in the wheel rim, nothing clearly leaking.

Bike is a K75S, 1986, not mine. I'm giving it some badly needed TLC for a good friend. If you look closely at this bad picture, you can see someone welded the rear end and there is a cut mark, similar to when you loose control of a cut-off saw.

I have no idea if should call it a day and just rip it apart and tear into it. It's bizarre, it has been here for a month and today, a puddle.

We have no history on this bike. I'm afraid he bought the bike that had a rear end ghost and now it's turned into a gremlin. Why would you weld the rear end there? It's never been crashed that we know. It did have a clutch explode two years ago, welding was required then.:dunno:sick
 
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If you don't see the housing leaking I bet the seal behind the brake disk is gone with possibly the bearing as well if you're unlucky. Take the wheel and the disk of and tell us what you see.

Or it could be a leak from your caliper. Could be very simple.

Regards, Rene
 
Here is my best long distance photo viewing guess:

The mar on the final drive case happens to be right where the tapered roller bearing on the crownwheel (ring gear) shaft is located. If the case was cut or broken and welded at this location it is purely pot-luck whether the internal machining for the roller bearing outer race is perfectly true with the machining in the housing cover for the big ball bearing on the other end of the crownwheel shaft.

If not it will stress the ball bearing and probably damage the seal in the housing cover. That appears to be the source of the leak. The immediate short term cure is to remove the housing cover, examine and possibly replace the ball bearing, and certainly replace the seal and big O ring. My problem with this approach is that if the roller bearing fails to sit true in line with the ball bearing the drive will just self destruct again.

It that was on my bike I would do one of two things: I would get a used final drive with a good case and check it out internally, and then use it; or get one and rebuild it with bearings and seals in the new case.
 
Yeah, I knew somebody was going to tell me what I already knew.

Here is my best long distance photo viewing guess:

The mar on the final drive case happens to be right where the tapered roller bearing on the crownwheel (ring gear) shaft is located. If the case was cut or broken and welded at this location it is purely pot-luck whether the internal machining for the roller bearing outer race is perfectly true with the machining in the housing cover for the big ball bearing on the other end of the crownwheel shaft.

If not it will stress the ball bearing and probably damage the seal in the housing cover. That appears to be the source of the leak. The immediate short term cure is to remove the housing cover, examine and possibly replace the ball bearing, and certainly replace the seal and big O ring. My problem with this approach is that if the roller bearing fails to sit true in line with the ball bearing the drive will just self destruct again.

It that was on my bike I would do one of two things: I would get a used final drive with a good case and check it out internally, and then use it; or get one and rebuild it with bearings and seals in the new case.

Thank you Paul. I think you are dead on the money. I was hoping somebody might have the mojo to change my mind about what I thought needed to be done.
 
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