well i get a ton of blow back from around the bearing and just can't get the thing to tune. i sealed everything else and figure it must be the source of my grief. this engine and i just don't get along and haven't from the beginning. i originally ordered it from team crc and it came in opened packaging with the shrink wrap off. i got about a quart and a half through it before i had to rebuild it... i'm just ready for something else, but if i can nurse if back to lfe with a new bearing (and that realy turns out to be the problem) than i will use it for practice and bashing....