Rode 400 miles this weekend in the Texas hill country on my '85 K100 after finally cleaning out my gas tank enough to get great fuel delivery, then snapped my clutch cable on the way home from work Monday. (This bike never strands me far from home, always breaks in a way that teaches me another lesson - in short, the perfect obsession...)

I ordered a replacement clutch cable and looked up how to replace it, but I see there's a lot of gunk on the clutch arm on the underside (see photos). 

Is this something I can just clean up, or does it mean there's a bad seal or something that needs to be rebuilt at the back of the engine? I'm not noticeably losing engine oil or gearbox oil but I'm not too familiar with what's down there. Also: I have a complete '85 parts bike, so I can swap parts if recommended. 

Any advice?

Looks mostly road grunge to me, though the darker colour on the clutch arm raises questions.

I'd give the area a good clean, then see if it seems to be showing oil leak evidence after that.

Bill

indian036 wrote:Looks mostly road grunge to me, though the darker colour on the clutch arm raises questions.

I'd give the area a good clean, then see if it seems to be showing oil leak evidence after that.

Bill

I'd say that your pics show definite evidence of an oil leak - you will probably find that the rubber boot is split, so the oil will probably be from the gear box. It doesn't take much oil to cover everything and that then acts as a dirt magnet to attract and accumulate road grunge and end up with that classic looking black oily paste covering everything.

As Indian says - first thing is to clean it off and then you will be able to either see the leak or, if it is very small, at least detect where it may be coming from. 

Personally, I would have a rubber boot on order anyway though as my money is on it being split

My money is on that boot as well.

Probably a torn boot but sometimes the bolt in the clutch arm is not seated properly in the hole of the boot.

The boot.  You probably won't see the split till the boot expands.  Not an expensive part.

TacKler wrote:The boot.  You probably won't see the split till the boot expands.  Not an expensive part.

Thanks - I cleaned it all up and the boot is clearly split.