Re: Counter balance?
The answer depends on the configuration of the crank, and engine. Inline or V, what angle of Vee, plane of crank 1, 2, 3. On a single cylinder engine, counterweight = 100% of the rod +50% of the piston mass. There is really much math involved in setting the mass of the counter weigh, RPM is a large factor, rod lenght, on and on.
My Wheels don't slow me down