Oil seeping from vent in rear drive

[sdemeyer]

Just drove 1800 miles from WA to NM and noticed oil on my rear tire and rim. Looks like it is comming from the top vent in the rear drive. I still have 1800 miles to go for the return trip. Bike still drives great and doesn't make any unusual sounds. Should I be worried about this or is this normal for 80mph,8 hours a day for 3 days?

 

Thanks,

Scott

[ericfoerster]

Was more than likely over filled during service. I've seen a bunch like that.

 

JMHO

[ShovelStrokeEd]

I wouldn't worry over much.

A tad too much oil in there will act like that as will certain brands of gear oil. That little biddy pinion gear and great big ring gear can whip up the oil pretty good.

 

Clean things up and go ahead and ride home. When you get there, pick up a quart of Mobil 1 Extended life 75W140 full synthetic gear oil. Put 250 cc into the rear drive, after draining the old, of course, and don't worry any more.

 

Seems the Mobil 1 stuff is not prone to much foaming.

[upflying]

I had Red Line Shockproof Heavy in my rear drive and it also blew out of the vent after a long ride. I tried removing some and it still did it. I now use the Mobil 1 stuff as mentioned and no more problems.

[KMG_365]

The Redline oil does not have the anti-foaming agents necessary to keep it from being whipped into a froth. When this happens it soaks the foam filter in the vent and any increases in altitude and temperature can force it out of the vent hole. This is especially prone to happen if you start on a cool morning at Furnace Creek in Death Valley at 100 feet below sea level and ride at warp 8-9 for an hour or so to find yourself at Panamint Springs at 2000 feet and the right handers all of a sudden getting REALLY interesting--DAMHIK!! In 2004 I counted three bikes burping final drive oil in the parking lot at Panamint!

 

This will also happen with the BMW or other recommended oil if you overfill it per the Service Manual's instructions. The Service Manual says to fill it "to the bottom of the threads", but this is too much. If you look into the fill hole you'll see a small metal tang at about 7:00 or so--this is the max-fill indicator and should also correspond to 250ml of oil. When draining, be sure the oil is warmed sufficiantly from RIDING it and when re-filling do not spin the wheel either as the oil is very viscous and will be carried up and around the housing taking a long time to drain back. This will give you a false-low reading and cause you to overfill as well.

 

Pop the plastic cap of the vent off (it just pulls up and off) and use a fine pair of tweezers to extract the cylidrical foam filter and clean it up. The filter looks just like a foam ear plug, but is not as dense a type of foam. Yours might have already been sucked into the drive and "consumed" so don't be surprized if you don't see one in there. Be sure it's clean and dry and stuff it back into the vent hole then replace the vent cap (point the vent hole in the cap towards the rear so it doesn't pick up too much additional road debris).

 

[Clive Liddell]

Jamie,

The position of "the hole" could develop into a healthy thread!

 

I position mine towards the rotor to 1) avoid water ingress when sprinkling bike 2) hopefully in an area where it's most sheltered from passing slipsteam

 

[KMG_365]

Jamie,

The position of "the hole" could develop into a healthy thread!

 

I position mine towards the rotor to 1) avoid water ingress when sprinkling bike 2) hopefully in an area where it's most sheltered from passing slipsteam

 

 

Goeie dag/Molo/Hallo, Clive!

 

What is this "sprinkling bike" of which you speak?? It sounds suspisciously like "washing" your bike!! Oh the horror!

 

But you're right, maybe we should start another thread for the snow-bound northern-hemispherians to give them a good argument topic to last them through the non-riding season!

 

BTW, how's your summer shaping up?

 

 

Hmmmm, let's see how anal-retentive we REALLY can get: Personally, I put mine at about 7:00 (when viewed from above), which I feel puts it sufficiently on the leeward side of the cap (when riding) and not too exposed to side winds from the right, and as the left side is protected somewhat by the wheel and caliper, I feel this is a good compromise.

 

Your thoughts?

[Clive Liddell]

Hi Jamie,

The greetings you used seem to come from Western Transvaal or Free State? Have you been there? In our neck of the woods it's generally "sawbona(sp?)" = "I see you"

 

 

It sounds suspisciously like "washing" your bike!! Oh the horror!

 

It's the unwritten and unstated peer pressure from the group I ride with - when I get to the Off and see the gleaming ~35year old Airheads and K's (as well as Oil and Hexheads of course) what can one do but drag a rag over the bike being used on Sunday... My car and other bike do not suffer this ignominy, however.

 

BTW, how's your summer shaping up?

 

We've had a few 38-40C days already but this last week has been cold and wet (for us anyway, night=16C day=20C).

 

Hmmmm, let's see how anal-retentive we REALLY can get: Personally, I put mine at about 7:00 (when viewed from above), which I feel puts it sufficiently on the leeward side of the cap (when riding) and not too exposed to side winds from the right, and as the left side is protected somewhat by the wheel and caliper, I feel this is a good compromise.

 

7:00 may be good for me but, as a reference, are you standing at 90deg or 180deg to the bike?

 

The last MotoGP a bit later will be worth being housebound for though!!