It is important to inspect your Harley drive belt and sprocket at each service interval. Inspect each tooth of the rear sprocket. Look for major tooth damage, large chrome chips with sharp edges, gouges caused by large stones or debris, and excessive loss of chrome plating. Harley suggests sprocket replacement if major tooth damage or loss if chrome exists.
Inspect every Harley drive belt cog. Inspect the Harley drive belt for cuts or unusual wear patterns, excessively beveled outer belt edges, signs of damage from stones or other debris, exposed tensile cords on the tooth portion of belt, or signs of puncture or cracking at the base of belt teeth.
Some edge beveling is common but may indicate that the sprockets are misaligned. If cracks or other damage exists near the edge of your Harley drive belt, replace the belt immediately. Damage at the center of the belt will eventually require that the belt be replaced. However, if cracks extend to the edge of the belt, failure is imminent and the motorcycle should not be ridden until the worn Harley drive belt and pulleys are replaced.
Typically, an excessively worn sprocket will be running against an excessively worn drive belt. They should only be replaced as a set and the set needs to include the front drive sprocket as well. Remember, the smaller, front sprocket has seen the same punishment as the rear. You never want to have a new belt running against a worn sprocket(s) or vise versa.
Use a belt tension gauge to measure drive belt deflection. A tension gauge will help to make sure a belt is not running too loose, which can cause “ratcheting” to occur. This is when the belt jumps a tooth and can cause tensile cord crimping and breakage in the belt. Set the correct belt deflection for your year and model. Check your manual for year and model but rear axle nut torque should be 105 ft lbs.