If you have an engine with high horsepower, my advice is to place the belt tighter than on average. A belt that is not tight enough can break easily. However, not many drivers tighten it to the tension that must be reached. If you can’t do it on your own, you have to ask a professional to do it instead of you or to show you how to tighten the belt. Each model has its own tension deflection requirements. For example, Harley Davidson Sportster needs 10 lbs force and ¼ inches – 5/16 inches deflection.