Timing Belts & Chains
About Timing Belts & Chains
Timing chains carry drive from the crankshaft to the camshaft or cams. When one stretches, the valve timing drifts, and you hear a rattle from the top of the engine. Riders replace the chain at an engine rebuild, after a noise appears, or when upgrading a chain that has been a repeat problem. Most items here are cam chains for four-stroke engines, and there is also a drive belt for older Polaris machines.
The product name tells you what to match. The series code, such as 92RH2015, 82RH2010 or 25H, gives the chain's pitch and style, and the link count, such as 110, 114 or 128 links, gives the length. Both must match your engine, and so must the type. Roller chains and silent chains are both listed, and an engine is built for one or the other. The Polaris drive belt is sized by width and outside circumference, for example 1-3/16 inch by 40-7/8 inch. Fit a new tensioner and check the sprockets for wear at the same time, using the timing marks in your service manual.
Brands in this category include D.I.D, Hot Rods, Parts Unlimited, ProX, Wiseco and Hot Cams. Pick your machine in the Ride Finder at the top of the page. To finish the job, look at Tensioners & Pulleys and Sprockets, part of Timing Components & Kits.
FAQs on cam chains and timing belts
What do codes like 92RH2015 mean in a cam chain listing?
The code identifies the chain's series, including its pitch and style. The number of links is listed separately, such as 114 links. You need both to match your engine, and the code alone does not tell you the length.
Can I shorten or lengthen a cam chain?
Do not assume so. A cam chain is sold in the link count your engine needs, and an incorrect length changes valve timing. Use the listed link count for your model, and only change length if the service manual says to.
What makes a cam chain wear out?
Wear in the pins and rollers lengthens a chain over time. Dirty or low oil speeds that up, and so does a weak tensioner. Changing the oil and filter at the interval in your manual is the best way to slow it down.
How often should a cam chain be replaced?
There is no single mileage. Replace it when the chain has stretched past the limit in your service manual, when it rattles, or when the engine is already open for a rebuild. Oil changes on schedule help extend its life.
Is a silent chain better than a roller chain?
Neither a silent chain nor a roller chain is better in general. A silent chain runs more quietly, while a roller chain is simpler. Use the type your engine was designed for, because the sprockets are shaped to suit one style or the other.
