Black Soot on Carbs

[Bert Patterson]

Carb question. I have K&Ns on an ’82 GS1100E. Recently, the #1 carb and air cleaner are getting dull black soot built up on the outside. From the pattern, it looks to be coming out of the pod and blowing across the carb. (I think.) Anyone got any suggestions?

[DimitriT]

Carb question. I have K&Ns on an ’82 GS1100E. Recently, the #1 carb and air cleaner are getting dull black soot built up on the outside. From the pattern, it looks to be coming out of the pod and blowing across the carb. (I think.) Anyone got any suggestions?

Are you sure its soot? Sometimes, when you close the throttles, a little gas vapor will back into the airbox (or in your case, pods) and deposit an oily film. This attracts dirt, which looks like soot. You can also get vapor leaking from the throttle shaft seals and the choke plungers. These are other places which get dirty. If the bike is running ok I would just clean them off with a little Simple Green and not worry.

[chef1366]

Where is your crankcase filter located? Over the Carbs?

[Bert Patterson]

Where is your crankcase filter located? Over the Carbs?

Breather?? Underneath the carbs.

I've only had bikes for about 40 years now, so my mechanical aptitude is limited (it'd be nice for me to start doing something about that before I'm dead, eh?).

[chef1366]

I wasn't trying to insult your smarts. I hope you didn't take it that way. You do have pod filters, right? I had my crankcase filter around my carbs and ended up with black soot on my pods. I moved it to where the airbox used to be and now I don't have that problem.

[Bert Patterson]

I wasn't trying to insult your smarts. .

Ha!!! Impossible. When it comes to motorcycle mechanics, I've got very little smarts to insult. Really. After all these years, it's pathetic, but true.

I hope you didn't take it that way. You do have pod filters, right? I had my crankcase filter around my carbs and ended up with black soot on my pods. I moved it to where the airbox used to be and now I don't have that problem.

I know what the breather looks like, but I'm not sure what the crankcase filter would look like. I suppose it may be obvious to me when I check it out. I look at it after I vanish from my office.

[chef1366]

If you have pods and removed the airbox there should be a seperate crank case filter. Follow the hose from the very top middle of the valve cover on the carb side and it should connect to a round filter.