My 130 mpg 2-stroke Minarelli bike

[renault_megane_dci]

For carbon build up, could you not play with a hotter spark plug ?

[xavi]

Mine doesn't buil up any carbon because I only use 2% oil, but if I use 3% it will probably build some...

I take the spark plug off every now and then, and give it a clean. and the center electrode is brownish as a good burn indicator should be. clean the little fresh oil, and with a steel brush I sand off the dry oil. but it was pretty decent with very little carbon...