captinjohn--thanks mate , i had a 16x10 apc on it , will try an 18x8 master soon , to add a bit more , i think it was george aldrich said the counterweight needs to equal the weight of the rod , gudion pin , and a "bit" of the piston . i think the killer with the ryobi is the steel rod , im going to make one out of titanium[not an easy task] ,but it will shure chop that weight down.
i obviously like smooth running engines.