I just got a 2001 Rm 125, not a kawi but i couldnt find one for the price.
I just rebuilt the top end and noticed on the left side of the head theres a hole, by the exahast port. If i fire it up exahast will come out of it and one time it acted like it back fired. Is this supposed to happen? or did something fall out? and body know, help would be appreciated! I know quite a bit, but not anything like this. Ive never seen it before.