Primary Drive Belts & Chains
About Primary Drive Belts & Chains
The primary drive carries power from the engine to the clutch and gearbox, and on the V-twin models in these listings it is a chain or a belt. Riders shop here when a primary chain has stretched or gets noisy, when a belt needs replacing, or when they want a belt drive kit in place of the stock chain.
Chains and belts are listed differently. Primary chains are given a size and length, such as #428-2 x 92, and the silent chains in the samples are listed as inner and outer chains in link counts for Twin Cam models. Belts are listed by width, such as 1-1/2 inch or 2 inch, pitch, such as 8 mm or 11 mm, and tooth count, such as 92T, 142T or 144T, and a replacement belt must match all three. Belt drive kits are listed by year range and style, including open belt drives, which run the belt dry. Whatever you choose, fit new gaskets and fill with the fluid your manual specifies.
Brands here include Drag Specialties, Gates, Feuling Parts, Belt Drives Ltd and Venom Products. Pick your machine in the Ride Finder at the top of the page. See also Primary Drive Housings & Covers, Primary Drive Kits and Drive Belt Pulleys & Tensioners, all part of Final & Primary Drive Parts & Kits.
FAQs on primary drive belts and chains
Can I replace a primary chain with a belt?
Belt drive kits are made for specific models and years and replace the chain drive with a belt and pulleys. Choose the kit listed for your machine and follow its instructions, because the belt, pulleys and covers need to work as a system.
How do I find the right size primary belt?
Match three things: the belt width, the pitch, and the tooth count. Check the old belt for markings and compare them with your service manual and the listing. A belt that is close but not exact will not run correctly.
Does a primary belt need oil like a primary chain?
It depends on the setup. A primary chain usually runs in oil in its housing, while an open belt drive runs the belt dry. Follow your manual or the kit instructions for what fluid, if any, goes in the primary case.
What is a primary chain tensioner for?
The tensioner or adjuster keeps the correct slack in the primary chain. Too much slack makes noise and wears parts, and too little loads the bearings. Set it to your service manual's method, and replace worn tensioner parts.
What are the signs of a worn primary drive?
Noise from the primary cover, metal in the primary oil, excessive chain slack, or a belt with cracks or missing teeth are all signs. Inspect the primary when you change the gaskets, and replace worn parts before they damage the housing.
