[Thermodyne]

The MR 103 is intended to be used in an otherwise stock engine. If you raise the compression, you may end up having to back out some spark. Offsetting any gain you made from the few points of added compression.

At most, I would try a thin head gasket. That way I could undo it, should it turnout to be problematic. If the heads are still on the scooter, I would not pull them for just to do that.

If you want to work on the heads, have them cnc'd and larger valves installed. The head flow is the power bottle neck on the 103.