The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Lucky_Lou on July 14, 2010, 02:53:41 PM

Title: Oil from Swinging arm Boot
Post by: Lucky_Lou on July 14, 2010, 02:53:41 PM
When i pulled the boot off i got a bit of oil from it about 1 tablespoon i would guestimate(see piccy) the gearbox level looks high and im wondering if thats what caused it, ive done 3000 miles since it was topped up (the guy that has Gerties wheels did the fluids with the Mot).
The Car mechanic in the workshop next to me says he wouldnt worry about it unless it starts leaking heavily whats your thoughts?.
Lou
Title: Re: Oil from Swinging arm Boot
Post by: montmil on July 14, 2010, 03:00:23 PM
Perhaps a bit of gear oil migrating from the drive shaft reservoir. You'd want some oil keeping the U-joint happy. Looks OK to me. If the transmission is overfilled, bringing it back to spec level may reduce the tablespoon of gear oil to no more than a teaspoon. Need some...
Title: Re: Oil from Swinging arm Boot
Post by: Bob_Roller on July 14, 2010, 03:13:34 PM
Every time I pull the boot back to facilitate maintenance, I always get about the same amount of gear oil .

I think it gets pooled in the boot pleats, then comes out when you disturb the boot during removal .

Personally, I wouldn't get concerned about it .

While you have the transmission removed, there is a small vent hole in the transmission case somewhere above the output shaft, make sure it's open, it vents the drive shaft cavity .

If it's clogged, the drive shaft housing can pressurize when things get up to operating temperature and force gear oil into the final drive .
Title: Re: Oil from Swinging arm Boot
Post by: Lucky_Lou on July 14, 2010, 05:27:07 PM
Thanks for the reasuring replies, i hadnt noticed the vent(is it inside the clamshell??) ill check it when i redo the boot just waiting for new jubilee clips from Motorworks as i stripped the old ones getting them off.
Lou
Title: Re: Oil from Swinging arm Boot
Post by: nhmaf on July 14, 2010, 06:15:35 PM
I'd just check that you've still got enough oil in the driveshaft housing - stick a small screwdriver straightdown from the top in the fill hole that is on the top side where the final drive bolts onto the black painted swingarm - It will touchdown against the top of the drive shaft inside - there should be enough oil at that location to wet 1 or 2mm of the screwdriver's tip  - this is done with the bike on the centerstand on a level surface.   If you're also good there, no worries.

I always find about that same amount of oil when I pull off my swingarm boot.
Title: Re: Oil from Swinging arm Boot
Post by: Bob_Roller on July 14, 2010, 07:23:29 PM
The vent hole, is just above where the transmission output shaft comes out of the transmission, it's accessible in the area that is covered by the rubber boot .
Title: Re: Oil from Swinging arm Boot
Post by: Rob Valdez 79 R65 on July 15, 2010, 12:19:00 AM
Quote
The vent hole, is just above where the transmission output shaft comes out of the transmission, it's accessible in the area that is covered by the rubber boot .

So it is behind the flange?
Title: Re: Oil from Swinging arm Boot
Post by: Bob_Roller on July 15, 2010, 07:54:12 AM
It's located in the back cover of the transmission case, above where the output shaft comes out of the transmission .
Title: Re: Oil from Swinging arm Boot
Post by: Semper Gumby on July 15, 2010, 08:33:42 AM
HI Lou,

If you use the stock amount of fluid to refill the drive shaft (150cc) and then you go out and drive for an extended time at high speed (70mph) the oil from the drive shaft will migrate through the vent hole next to the top of the gearbox propellor seal into the gear box.  If you refill the drive shaft with less (100-125cc) of gear oil then this will not happen as much.  

Don't worry about running with less oil.  Oak Oakenshield says it will work fine with just 50cc or oil.

Good luck.
Title: Re: Oil from Swinging arm Boot
Post by: Rob Valdez 79 R65 on July 15, 2010, 06:33:52 PM
Quote
It's located in the back cover of the transmission case, above where the output shaft comes out of the transmission .


But inside the boot area?
Title: Re: Oil from Swinging arm Boot
Post by: Bob_Roller on July 15, 2010, 07:24:40 PM
Yes !

It's a small hole, on the order of .025-.030 inches in diameter .