Twin Cam 103 HD Drive Belt Deflection

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It is important to check HD drive belt deflection at every service interval and as part of your pre-ride inspection. Belt deflection should be checked with the motorcycle either upright or on the kickstand without a rider and without luggage.

Finding the Tight Spot

Before checking deflection, you need to find the tight spot in your belt.The best way to do this is by raising your rear wheel and and spinning the wheel until the tight spot is apparent. At this time, you should not only be inspecting your belt for excessive damage or wear; you should also be inspecting your front and rear pulleys for excessive wear.*Refer to your year / model manual for the spec on tightest spot vs. loosest spot.

Setting Deflection

Once the HD drive belt tight spot is determined and the belt & pulleys inspected, you can lower your rear wheel and test deflection. Set your deflection gauge for 10 lbs (of force) and reference the deflection graduations in the window of your lower belt guard to determine the specified measurement as found in your service manual. You can also set your gauge to 10 lbs and read your deflection measurement on the gauge.

Important Part of Service

Correct belt tension is critical for the longevity of your belt and pulleys.Belt inspection is an important safety check that should never be overlooked. Make belt deflection part of your pre-ride inspection.

Next Up: General Harley Lubrication Points