1/8-1/4" Carbon in Exhaust Pipe.

[mlhend1]

I recently changed from the stock pipe to a FMF Fatty pipe. Upon removing the stock pipe I noticed about a quarter of an inch of solid carbon inside of the pipe, at least where it meets up with the engine. I bought the 1994 KDX 200 with 500 miles on the odometer last year. It was about a half year before I changed the jetting and plug (to br8eg) to get it from running so rich. I also switched to Mobile 1 Sythnetic 2 cycle oil 40:1. What causes the carbon and what can I do to help eliminate carbon deposits in my new FMF pipe? Thanks!!!

 

[mlhend1]

Also, what is the recommended way of getting rid of the carbon deposits.

 

[mlhend1]

Someone suggested removing the pipe, plugging one end filling it with water, plug the other end and let sit for a few days. Scrub with a steel brush. Is there a better way?

 

[CaptainObvious]

If you jetting is correct you will get very little of those carbon deposits. Before I modified my bike (including proper jetting) my stock pike was choked with carbon. My modified bike has always had a clean pipe.

Carb cleaner or oven cleaner works OK on carbon.