differential fires

[Isamemon]

in another thread someone brought up that the BMW rear ends can catch fire
while I am rather new to BMW yet ride an old airhead, was wondering if this is somehting that happens ? what causes it ? How to prevent it ?

[Motor31]

HHHmmmm, I've never heard of, or seen that in an airhead or K. :dunno

[widebmw]

I know a guy who had his rear disc brake catch on fire on a K bike.
This was maybe 1992.

[BubbaZanetti]

only picture i've seen is of a new R12GS, never from an airhead with monolever suspension.

[riderR1150GSAdv]

What caught fire was the rubber boot that seals the gap between the FD and the paralever arm. My guess is a seized bearing that overheated the whole FD enough to start that fire. I saw the pics on Adv rider as well.
Personally I wouldn't lose much sleep over it ,as it is very rare.

[GregFeeler]

in another thread someone brought up that the BMW rear ends can catch fire
while I am rather new to BMW yet ride an old airhead, was wondering if this is somehting that happens ? what causes it ? How to prevent it ?

I've been riding BMW's for 30+ years and have never heard of such a thing ever happening. Run the rear end out of lube and it will get hot, but the only thing to burn is the rubber boot between the rear drive and the swing arm, and not all BMW's have that. Urban myth. :brow

[dbrick]

I can actually speak to this, as once my dealer neglected to refill the rear end at a regular service. With the rear end dry, the bike ran almost 4000 miles before the gears turned to crinkley. When they failed, the case was warm, but not hot.

[Isamemon]

thanks for clearing that up for me,
the thread was in the thread asking about stainless brake lines

[robsryder]

... rear ends can catch fire...
There is more than one way for this to happen.

On the AirList a similar phenemonon can be observed from Moly.

If you are gonna use it (Moly), remember that just a dab will do (5% by volume according to mfr).

I use it in my airhead transmission, driveshaft, and rear drive unit. Some airhead gurus believe that Moly is bad and can cause problems, particularly if misused (e.g., too high a concentration). At least one airhead guru believes that the addition of Moly can help alleviate some rear drive issues (although I think that he was speaking about the new oilheads).

The Moly I'm speaking of is molybdenum disulfide sold by DOW Corning as M-Gear Guard, Part # 1897519-0594, also known as Molykote. Call Dow-Corning at their toll free number (1-800-248-2481). If you call Dow and give them your Zip code, they can look up the local supplier for you. Or you can click on the link below and enter your state to find a local distributor.

http://tinyurl.com/eswwk

[James.A]

While I've never seen it on a bike, I did see that once on the side of the road underneath an F-150.

Bearing on the differential input shaft failed.
Differential housing got HOT.
Caked on leakage/road grime ignited.

[PeoriaMac]

I did see the picture on AVRider, which showed the R1200 burning brightly.
It says something about us when we spot a fire on our bike and whip out the camera first thing.
"They're never gonna believe this back at the shop"....

Mac

[kbasa]

The Moly I'm speaking of is molybdenum disulfide sold by DOW Corning as M-Gear Guard, Part # 1897519-0594, also known as Molykote. Call Dow-Corning at their toll free number (1-800-248-2481). If you call Dow and give them your Zip code, they can look up the local supplier for you. Or you can click on the link below and enter your state to find a local distributor.

http://tinyurl.com/eswwk

Big fan and long time user here. :thumb