black deposit on exhaust pipes

This normal. What it means is that at idle or cruise, you are a touch richer than needed. Or that your exhaust is a bit restrictive, leading to a bit less scavaging than the engine wants.

If you look at the plugs, you should see a nice brown color on the insulator. If you are still running the original plugs, they will be black - from break-in.

On mine, a good bit of it went away when I did the header mods. But then again, I am always playing with the bike and its tuning. My plugs run a nice tan color.

I hope this helps.

Thanks again for the info Devious! I saw this and it made me think about the carbon I get on my stock pipes. Will removal of the pre-cat clear some of it up??

I noticed a bit less on mine after the precat removal. I have also added fuel at cruise and reduced it at idle.

I just went out to the garage to look at the ends of my silencers. the right one has a very slight dusting of soot. The left one is clean. The bike has about 200 miles on it since it was cleaned. SO, I guess it does reduce it a good bit.

It make sense that without the cork in the collector, and a decent tune, the engine is more efficient now.

zmann said:

Howdy,
I'm using the 20102Tune_dyno with arrow pipes. The engine is smooth now, idles well, and pulls evenly from the bottom but I notice a little bit of black deposit around the ends of the cans. This means I'm running a bit rich, right? Possibly starting to foul my plugs? Any suggestions from the gurus out there on specific changes to be made in tuneboy? I'm a bumbler in those maps.
Once I finish emulating a few more of Devious2xs' simpler changes (thanks for all the info!), I'll probably find a local dyno-tuner.
ZM

Click to expand...

You could try the map I have been developing. It is based on the 20102Tune_dyno. You can find it in the downloads section. It has leaner cruise at small throttle openings and midrange at wot. The ignition map is slightly modified also.

Devious2xs said:

If you are still running the original plugs, they will be black - from break-in.

Click to expand...

Are you saying I should change my plugs? I have 900 miles logged.
Thanks,
D