FD fluid - breather misting

[GTSDave]

Hi all;

I had a misting problem with my FD and fixed by just switching to a different fliud.

I have an 04 1150RT; rebuilt FD by Charlie that failed on me in the 09 IBR at 100k mi, been fine since save for recently (past yr) it "pucking"/ misting out the breather. I talked to Charlie about it and did overfill once by turning the wheel/ gears and added a little more. But next change carefully measured the right amount, changed the O-ring and sponge to no avail - was still oiling up my rear end after 200-300 mi. I was using Bel-Ray 80/90W gear oil, which is the weight trhe manual specifies.

My local BMW dealer sold me recommended fluid which is 75/140W Motorrad Super Synthetic GL-5 gear oil - $23, but my problem disappeared. I just did a two day rally in NV recently where I did 3+k mi in 4 days counting there and back home, some if it triple digit speeds on some lonely NV hwys and not a sign of misting. Couldn't be happier and I don't look at it as expensive as a quart will last many years due to the small amt used to change the FD.

I am simply amazed that just switching fluid brand/ weight cured the problem. Inow have 150k mi on the bike and running strong.

[dirtrider]

Afternoon Dave

 

 

 

Per a BMW service bulletin the oil quantity is just an approximation. The actual fill level is not by amount but to the very bottom of the fill plug threads with the motorcycle on the center stand.

 

There was also a BMW service bulletin on some final drives with the vent hole made too small therefore capillary action (& bridging) was causing spitting some gear oil out. The bulletin I have was for earlier oilhead bikes but it also mentioned the possibility of later bikes possibly having that issue as they (BMW) wanted a dealer notification sent in if vent misting was noted on any later bikes.