Final Drive Vent

[Sunbeemer]

After all these years I learned that the plastic vent cover on top of the final drive may have been responsible for the leaking grease seal at the input shaft I've noticed from time to time . After a good ride on a 50 degree day there was more of a stain around the rubber boot than I'd ever seen so I figured the seal had finally given up , but while cleaning the mess I noticed the final drive's plastic vent cover wouldn't spin freely, so I gave it a twist to unfreeze it and took it for a good ride and it didn't leak . So I guess I'll just give that plastic cap a twist every now and then to make sure it's able to vent the pressure that builds up when the final drive warms up.

We all probably need to vent from time to time!

[sweatmark]

Good tip. My current Rockster has the telltale rubber boot stain, and the bike is still low miles. Will check the vent.

[riceburner]

Good tip!

[towerworker]

That vent has (or should have) a foam filter. Years ago my bike fell over and I later realized that filter became saturated with oil. Started seeing FD oil seeping out of the vent after the Fd heated up. The oil saturated foam would not let the pressure vent and as a result oil pushed out. I removed the foam, washed it out and reinstalled. That ended the problem.

[Sunbeemer]

That's good info. I removed the vent cap a few years ago to see if there was a filter in there, but there wasn't. I figured BMW would've put a filter there (being Germans and all), and am happy to learn they did. I'll find something to keep the dust out.

BTW, I dropped the bike on it's right side a few months ago when a newbie pillion bailed off the right peg before I had both feet down.
Didn't think about that maybe plugging the vent cap till you mentioned it. Thanks!

[riceburner]

How does the cap come off? Does it just unscrew?

[Mr.Frequent]

Good news! Who doesn't love a simple fix ?

[Sunbeemer]

How does the cap come off? Does it just unscrew?

Just takes a good, hard tug straight up.