Crankshaft Balancing - Build-Off - Greg's Bike

I had just received the polished motor from J&D Polishing and was about to start assembling it when I realized I needed to balance the flywheels first. I started asking about crankshaft balancing, eager to find a capable shop because I know how much balancing reciprocating mass can affect a motor's performance. Plus, this particular motor has an untested mounting system-the existing mounts should be more then adequate, but reducing vibration also reduces fatigue on the metal and the rider.

Eventually, I asked Brian Nallin at Revolution Performance based in Plymouth, Wisconsin, if balancing my crank was something they could do. He replied, "Of course we can, haven't you seen our website?" Then he promptly brought me up to speed on the most advanced crankshaft balancing techniques: dynamic, instead of static, balancing. Dynamic balancing actually balances a crank while it is moving, while factoring in the weight of each piston. Think about how wheels are balanced nowadays, on a machine that spins it at high-RPM to make sure it is spinning with little or no vibration or wobble-the same principle is applied to the flywheels of a V-Twin. Every vibration can be attributed to a loss of power, all vibration is misdirected power-smooth is always better.