Angle Gearbix Rear O-ring leaking

[ride4fun]

Hello,

One of my 2004 R1100S has the O-ring on the rear angle gearbox leaking. How do I change it? I am not able to remove the cap. Am I supposed to pull it hard?

[908/930]

Is there a chance you have overfilled your final drive?

[ride4fun]

I am going to check that over the weekend - but it started leaking halfway through a weekend ride (that involved a lot of leaning - Cherohala Skyway in TN). I guess, I still would not expect it to leak - unless it acts as some kind of pressure valve.

[908/930]

Yes that is the case vent, so if you were leaning far enough that could do it. Still check fill level.

[ride4fun]

OK Thx

[BigDav]

I'd plan on replacing the fluid. The vent is there because the fluid expands when it gets hot and it prevents the other seals from leaking because of the increase pressure.

The hot fluid could have broke down the anti foaming agents in the lubricant.

[RBMann]

On a trip across NV and UT I was running hot and fast when the special pink goo final drive fluid start coming out of the breather. I had to add an extended hose to vent out to a safe place. Should have just changed to a different fluid.

[Jozef Schumann]

On a trip to Goldfield, Nevada - My 2003 'prep' with enhanced capacity fuel tank was between 125-135 MPH for 170 Miles nonstop on a 100f day without issue. For those who do not know that stretch, between Ely and Tonopah (and adjoining routes) - there is only you, the road, and not much else save for the random kamikaze reptile. These are under-stressed machines and will happily motor along at speeds the vast majority of owners never exercise, at least not for miles and miles on end.

Final drive oil capacity is approximately .25L or just over one quarter US quart. The factory shop manual specifically states draining the lube when at operating temp. This is critical as sufficient draining of the used, contaminated lube is not possible otherwise. Final drive leaks have never been a factor.

Now, I have indeed noticed the unmistakable odor of Diff/Trans lube at times, usually when stopped after some significant sorties, but this is simply attributed to the vents - both - atop the transmission as well as the final drive, doing exactly what they're designed to do.

Personally, I have a helper hold the bike upright on level ground as even the slightest angle deviation results in an inaccurate assessment of "To bottom edge of the filler opening"



Lubricant's are a rabbit hole topic, however - This is what I use in my boxers and it has proven to be exceptional for over 150K grueling, mercilessly beat upon miles. Of course, any brand is suitable as long as it meets the manufacturers requirements and service intervals are strictly adhered to.





J.S.

[Swamper]

Not much happening in Goldfield, usually just ridden through on our journeys. We stay in Tonopah and Ely often. 150K on a S is impressive. Makes me want to try to ride one of mine to the TOTR this year.

[ride4fun]

I checked the fluid level and it's fine. The oil looks new as well (I only had 2000 miles since I changed it before). I am going to change it anyway and monitor the situation.

I black cap pops up with a screwdriver - everything looked ok.

Thanks for the feedbacks.

[850dunstall]

the pink goo color begs the question.

the final drive calls for 75w90, and there have been problems when heavier weight oils have been used.

[ckcarr]

Pink would be from Red Line gear oil.