First off, never again.... every day was a call with drama and a problem with the bike when there was no issues when he got the keys...
Talking to him sounded more like the bike was on a track session rather than a borrowed friends tour...

It varied from gears jumping to brake fade, to no tread on tires to rear drive leak (which is this post)
My 2nd gear jumps if you are wacking the hell out of the throttle. It has for over 30k now, a bent dong bone I'm guessing. If you are riding sane, there is no issue.
Brake fade... I did that once at SFO around 2008 or so with not so sane street riding and cooked the front to the point of boiling... Ha said he had fade on the REAR "backing it in" REALLY?!!

Tires, had 1750 miles on them...., but I guess when you tell me you are doing 120 in 95 degree heat and stil getting passed, the rubber goes quick.
So now to the point of the post...
I think it is road grime, my oil level is good and so is my pumpkin, but there is a grease type coating along the pumpkin sidefrom the kick stand back and the inside of the rear wheel.
Is there any place that could have a leak other than the pumkin of oil?