final drive oil useage.

[Crazy Miles]

What will cause useage of 1 oz, and for it to darken to black after 23K. I can undstanstand the black color, however  to use it with no leaks has me worried!  Mobil 1  syn  75/w90  ??   

[Ricky-D]

1 ounce of liquid is a small amount so I would think your method of determination for usage may be faulty.

You should see evidence of leaks if there is an actual loss of lubricant.

***

[valkyriemc]

Most have found the original fluid, dark. Haven't ever read/heard about susequint changes being dark.

[John Schmidt]

Replace it with a good synthetic when you do. Let it drain out real good, then pour some fresh in and let it run out as well. It will run out partially dark, then close it off and fill. The final drive will also run cooler with full synthetic.

[bentwrench]

The black stuff is a moly coating applied to the gears for break-in.It coupld lose an oz.or two to the pinion cup o-ring if it's not sealing.
bw

[Earl in Pensacola]

I would suspect that it was 1 oz. short of being full to begin with.  Drain and refil to the point that the 80/90wt will just begin to run out of the hole with the bike straight up level.
IMHO

[Jabba]

Aren't you supposed to change that oil about every 10K?  I do.  It's CHEAP.

Jabba

[Earl in Pensacola]

just change it along with each new rear tire-- for me that's about every 18K and it's never been a problem-- Just use a good high quality 80/90wt and my '97 is up to 241K.