Originally Posted by
1995 Monster T
The black stuff is from not enough oil lube. and high nitro content. Add more oil lube and you will be fine.. All my engines are clean from using the correct amount of oil lube 18%. You can clean it off with oven cleaner and a scotch brite pad.
The black stuff is for a part a burn of the dirt in the castor oil because castor oil is hard to get pure and for a part the burn of the oil itself.
Has nothing to do with a low oil or an high nitro content to do. Well..... for a part. If you run a high compression with a matching cold plugthen there is a slight cleaner burn.