Gear oil leaking out of rear drive relief port? (K75S)

[jbs80106]

A few weeks ago I pulled my bike apart to check splines and re-assembled.  Didn't know that gear oil in the rear drive would leak out but it did, so I just drained it all out.  Refilled with .260ml (what I recall from the manual).  It filled up nearly to the top which I assumed was right.  The manual gives you the total quantity of gear oil capacity, but doesn't say what the level should look like when looking in the hole.


So, now I seem to be getting gear oil coming out of what I believe to be the relief valve?  It's a black cap covered nub sticking out of the top of the rear drive.  Not the speedo cable, not the fill hole, but above that.

Does that mean:

A) It's overfull and bleeding out like it's supposed to?

B) Something needs tightening?

C) Something else?



If its over full, if I let some out, how will know how much to drain?  Is there a sight glass I haven't found?

Or should I drain the whole thing again and refill?  

Thanks!!!!!!!!!!!

[rgbeard]

I can't speak from BMW experience, so perhaps someone will come along and add some.

Insofar as Honda Goldwings:

Procedure is to add to the bottom of the filler hole.  It's appx 5oz of oil.  From what I know, most mfgrs use the bottom of the fill hole as the measure.

I've never seen oil spray out of the relief hole following a fill, but I'd only worry about it if it continued after 20 miles or so.

[Justin]

but I'd only worry about it if it continued after 20 miles or so.

or if it's leaking on the tire  

[Tar Snake]

I think you just over filled it. On the K75 put the bike on the centerstand and fill until you just see the oil level touching the lower thread or 2 of the fill hole. Anymore than that and it pukes out the breather and makes a mess.

BTW if you don't have the Cylmer manual for the K-series get one, its full of all kinds of tips like that. It was really written for a guy out in his garage, not a BMW Technician.

[jbs80106]

Thanks!  DO have the Clymer and it's great.  I just filled through the speedo cable hole before putting her back together....see what happens when one doesn't follow directions and takes short cuts?!?!  

Sounds like if I pull the fill hole screw the excess might spill out all over till it gets to the proper level, or I can try to drain through the drain hole till its at the right level!

You guys are brilliant!