Final drive leaking oil

[F14CRAZY]

During my mostly-daily tire check today I noticed that my final drive is leaking (seeping) oil. A minor leak but definitely leaking. I think you call it the ring gear seal, but it's leaking onto the wheel from behind the brakes.

I happened to be making a trip to BMW of Grand Rapids and asked the service guys (well the owner) how much it would be to replace. He said that they replace the bearing along with the seal because a bad bearing is what makes the seal go bad.

That makes sense to me but I don't feel any play in the final drive.

At any rate he said $2-300, which I suppose isn't bad. I found a good forum post and want to try replacing the seal and perhaps the bearing myself though...

http://www.k100-forum.com/t5697-how-to-check-and-replace-the-final-drive-crown-wheel-bearing-and-seal

What do you guys think about having to replace the bearing too? Is it best to just go ahead and do that along with the seal? I figure the bike has around 125k miles if that makes a difference.

Parts aren't cheap tho...seal is like $36 and bearing is like $133 (from the dealer). I figure for the seal I could probably take it to NAPA and find something compatible that's a lot cheaper. The one near me is the regional warehouse so they have most everything in stock.

Thanks guys

[billday]

I did mine myself, which means it can't be all that hard:

http://www.motobrick.com/index.php/topic,580.msg9690.html#msg9690

I did not replace the bearing. Replacing the seal only has fixed my leak so far (four years!).

Also, the thread you linked to shows a K1100, very different from your monolever K75. See the document cited in my post for the Monolever howto.

[johnny]

greetings...

before you decide to replace the seal and o ring like billday has so eloquently demonstrated... you gotts to ask yourself... will i getts lucky like billday did with just the seal and o ring or is there more whack in there causing the seal to leak...

humm... the dry arid rattlesnake on a 105 degree day isnt where i wanna figger out i shoulda done a full rebuild...

every final drive failure i have experienced has had the juice running out on the brake rotor... butts mine were self evident... cause the bearings where completely grenaded... in retrospect... even it it appeared just to be the seal... i woulda done the whole shebang anyway... 3 hundert dollars is a lot of ammo... butts id rather have a worry free final drive on the rattlesnake than another 1000 rounds of 45 waiting on isis at home...

so dood your doodillergence...

j o

 

[Scott_]

+1 what Johnny said.....

or do some looking on-line for a good used complete final drive, just a thought.

[billday]

Is it different with monolever and paralever FD's? Perhaps paralever FD's are more likely to have the bearings go.

Or maybe I am just unbelievably lucky. So lucky that doo dillergence doesn't apply to me.