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To improve reliability and performance of the motor, the crankshaft was checked for runout. If the crank has too much runout (or wobble) bearing life is compromised, and the cases will wear, losing their ability to hold the crankshaft securely in the cases. We trued the crank to reduce or eliminate runout. The crank was then welded to the crankpins to prevent it from spreading or twisting. Plus, the trued crank uses less of the engine's power to rotate a bound rotating assembly, allowing the combination to put more power to the ground - not to mention piston timing. Making sure the cases are within tolerance at the main bearing area is essential. If the cases don't hold the crank securely enough, the crank will move in the cases and break the right-side main bearing at the snap-ring groove. The snap ring is designed to locate the crank, not to hold it in place. To prevent movement, the cases must be in perfect shape. We installed the crank with Loctite Stud & Bearing Mount for further protection.