exhaust carbon buildup

[maddog]

I have a polini exhaust pipe that's completely rebuildable, after 4yrs and 20,000 mi. I had a lot of carbon, carb is jetted perfectly- oil pump also adj. using syn. oil, so I wonder if 1 piece pipes should be replaced every 5 yrs. I did replace the contessa kit with a MHR kit and a hotter plug to reduce blow by gasses.

[Wheelman-111]

Greetings:

I guess it depends on how many miles one rides in those 4 or 5 years. I probably have a total of 6000 in 7 years since I started goofing with these endearing 50cc (or 65, or 72,or 82 or 90...) bikes. It doesn't matter, because I've never held onto a pipe for more than a year anyway.