i ran my dads (romax) buggy this past weekend and the track had some rocks coming up and i landed a triple and sparks start flying out right where the fly wheel was and didnt stop till i landed the next jump. must of been a rock in the fly wheel because it was a little slower between the two jumps. i bet thats what it was. did you look at it good? if so was there any sign of something messed up? if not it should be just fine. i have seen a few mugens do it alot. its something to do with their breaks, talked to team drivers about it. its a number of things it could be but it should be just fine.