Do I need to worry about this leak?

[Muneio]

Ok relatively new BMW owner here I've been seeing and reading all these FD issues or non issues depending on who you talk to. I've got a small amount of weeping coming from FD boot does this look like it's something I need to worry about? This was after a 200 mile ride today was clean when I started
04' R1150RT Thanks Bill

http://Billhere.smugmug.com/photos/201202232-L.jpg

[alien_hitchhiker]

What's it smell like - gear oil, grease or road tar?

If it's gear oil then definitely be worried. That would suggest a leaking FD seal.

If it's grease, has the rear U joint been recently lubed or worked on? If yes then maybe it's just excess lube flinging off. Check the boot to make sure it's tight.

If no, then I think you have to consider that the U joint is heating up due to friction (i.e.; impending failure) and liquefying the lube. You might consider inspecting that rear U joint.

I'd be tempted to clean it off and take it for a careful ride on quiet roads. I'd then inspect it for any additional leakage and I'd feel that whole area for excess heat. I would never advise anyone else to do that though - because if that joint fails it could give you a world of hurt - and it still wouldn't guarantee that everything is OK.

If it seems to be road tar then clean it off and go - but keep an eye on it in case you're wrong.

Keep us all posted on how this plays out.

[alien_hitchhiker]

You know...the more I look at that the more it looks like it was flung up there from the road. Are you sure it's leaking out of the boot? If it were I'd expect it to have more of a stream pattern - like a drop of water moving across a windshield. Are there any traces of that same crap on your fender?

[DarkCloud]

Has your bike been washed with a high pressure sprayer lately?

Crazy JON

[Muneio]

It's definitly not from the road. been noticing it for awhile and have cleaned it off more then once Just looked and it sure seems to be coming from the boot. the boot has crude/oil? on the bottom of it and it seems to be weeping from both sides but primarly from the small rear side. The previous owner supposedly just had the 18,000 mile service done right before I bought it but I have not verified that with the dealer.

No high pressure wash since I've owned it.

[alien_hitchhiker]

Worry

[timmer66]

My 2000 RT leaks from thesame place, mainly on long rides when its hot out. Asked my dealer in Sturgis if I sould worry, said to watch FD fluid. I was told its a seal and keep an eye on it. Fluids never been low. I have about 28000 on it and will most likely have it fixed at my 36000 service.

[PGlaves]

That looks like a leak from either the final drive pinion seal or the transmission shaft output seal.

I would detach the boot at the front (swingarm) end and fold the boot back. Look to see if there is a trail of oil along the bottom inside of the swingarm from the transmission back. If so - suspect transmission seal. If not, suspect pinion shaft seal.

Then thoroughly clean the inside of the boot and final drive where it attaches, and put the boot back. If the seepage comes back quickly then you need to have the offending seal replaced. If it doesn't reappear for a while then keep your eye on it and make the replacement a winter project.

This is not the point of leakage that signals an impending final drive failure.

I would frankly be more worried about a transmission shaft seal leak than a pinion seal leak.

[Muneio]

Thanks Paul I will give that a try.

Bill

[Muneio]

Pulled boot back cleaned it all up. 160 mile ride today no signs of leakage so far.

[RTNewbie]

That stinks of a transmission seal failure. Is your drive shaft all oily? have you noticed the transmission lube level dropping?

If the answer is yes to either question, get on it asap so it (the oil) doesn't rinse your moly lube from the splines on your drive shaft and subsequently ruin everything.

[DrPaul]

Ok relatively new BMW owner here I've been seeing and reading all these FD issues or non issues depending on who you talk to. I've got a small amount of weeping coming from FD boot does this look like it's something I need to worry about? This was after a 200 mile ride today was clean when I started
04' R1150RT Thanks Bill

http://Billhere.smugmug.com/photos/201202232-L.jpg

90% likely it is the pinion seal. Mine does the same thing. It is not road goo. This is often a result of overfilling the FD or a blocked vent (the little black thingy at the top of the FD housing allowing pressure to build up in the gear case. I have noticed that if the FD fluid level (measured with the bike on the center stand) is at the top of the fill plug threads it weeps more than if the level is just below the bottom thread.

Dr. Paul

[PMonk]

I have a small leak that would just show up as a black oily spot on underside of at the rubber boot.

I was using synthetic oil in final drive. Now am using conventional oil in final drive and the leak has almost completely stopped. It has been this way for about 25k with no change so I just clean it off and ride.

[RogerGS]

I just had this exact same thing happen to my bike. 05 gs. Went on for a couple months and had it repaired with the 24,000 service.

It was the fd seal. In those two months I watched the fluid oil and it never really went down. Dealer said when he took it apart there was about a t spoon amount that had gotten through.

Roger