I have recently researched modding engines and have found some research.....As far as modding the crank I will stay away from that...There is a couple things you can do to the crank without throughing off it`s balance,but only on cranks that are stock and don`t have any factory work already done to them..Anything more than this and you will need to rebalance the crank and fill with putty...
I would recomend practicing on worn out sleeves,cases and head buttons.You need to get the feel for the correct speed to run the dremel at..After you have practiced and get the feel for the dremeling speed(along with a steady hand) only then would I proceed to mod a budget engine.Why a budget engine..It`s easier to seen gains and if you mess it up its a $100-$150 mistake and not a $300+
I will take little material off at a time...Its easier to take material off,cause you can`t put it back on