V-Twin cranks are built heavy, but can easily become out of balance from even standard use. This misalignment causes excessive vibrations and shaking, loss of power, and greatly decreases main bearing life. Loud noise from the crank case can be caused by a scissoring condition (when flywheel halves are no longer aligned) which is very common among used engines. Additionally, excessive play in connecting rods can also lead to catastrophic failures. A trued, welded, and balanced crank is more efficient, increases power, and runs smoother. Taking good care of your bottom end will extend surrounding components’ life expectancy, so more time on the road and less time in the shop! Remember: ALWAYS balance your crankshaft when increasing displacement!!