?leaking fork "seal" R1100R

[dhb]

I've got a 1999 r1100R. After a very spirited ride along some rough pavement (Foxen Cyn/Cat Cyn) working the front suspension out, I noticed some small amount of oil just above the "seal" on the left fork. The metal tube is free from dings, bug crud etc. I know this isn't a true seal, but haven't seen much about these things. Is it time to trade up to a K12R?

Dave

[Ken H.]

Well if your looking for an excuse for a new bike, I guess a leaky $6 fork seal is as good as any!

 

OTOH the seal is a easy replacement. There was a thread here about doing them not to long ago. A search should find it.

[upflying]

I recently replaced one on my right fork leg. It involved removing the handle bar, upper fork tube bolt, front wheel and the three bolts where the fork tube attaches to the lower control arm. Slide the fork tube out from underneath. Remove the slider from the fork tube. Pour out the old fork oil and remove the dust seal, spring clip, washer and finally the seal from the fork tube. Hardest part of the job was prying out the old seal and pushing in the new one. Reassemble with 1 pt of new fork oil and bleed the fork tube of air as you slide it into the fork slider. I bought two seals from BMW for $18 but only used one since the other fork is not leaking yet.

If you are doing both, do one at a time so you don't mix parts.

[dhb]

thanks, Ken. I guess I wanted to know what might happen if I just ignored this whole thing. Could I do enough damage that way to be sure that a new bike is the only reasonable solution?

D

[dhb]

thanks, Bob. I am in a dealer service situation I think with limited repair tools and time where the bike is. I'm trying to figure out if it's a BIG problem or not.

Dave

[upflying]

Not an urgent repair problem, I rode mine with a leaking seal for about a month with no ill effect.

[smiller]

Easy fix. In the meantime I wouldn't worry about it... it will take next to forever to lose a significant amount of oil, and the fork oil level isn't even all that critical in the telelever anyway... mostly a cosmetic issue (unless oil really starts to gush out, very unlikely unless you ignore it for a few years.)

[Green RT]

I had the same problem (leaking seal on right) on my 1999 RT. I just replaced the seals on both forks this afternoon. The whole job took about 4 hours (I work slowly and carefully). I do have a few questions:

 

Do these forks serve as shock absorbers? Is there another shock absorber built into the telever? There is a pin hole that regulates how fast the inner tube can slide in the outer tube.

 

I haven't seen any maintenance procedure that specifies replacing the fork oil fluid. Mine was pretty black. Seems like it would be a good idea to replace it occasionally. Is there a spec for this?

[smiller]

Unlike most standard motorcycle suspensions the BMW telelever fork tubes have no springs or dampening ability, those chores are taken care of by the single strut mounted between the telelever A frame and the bike frame. All the telelever fork tubes do is locate/steer the front wheel, and the fluid inside is just to provide some additional lubrication... and so the weight of the fork fluid isn't critical. I'm not aware of any BMW-specified replacement interval but it's probably not a bad idea to replace it after many years. Mine gets replaced whenever the fork seals fail

 

Also note that some fork fluids have compounds in them that make them appear very dark, even black, right out of the bottle, so color is not a very reliable way of determining age.