Originally Posted by Roelof

Handlapping is taking out the piston and use a polishing pad to polish the side wall of the piston. It is easy to do but you do need to be carefull.



It does help and with any other nomal engine just a few tanks on the track are needed to make it race ready but with the 2104 it seems that even then 2 litter is needed. I have no experience with it but many OS users doing their 1st 2104 are misjudging how much break in is needed compared what they normally have experienced.