Chains, Sprockets & Driveshafts

Is your chain stretched, have your sprocket teeth become pointed, or is a CV boot cracked? This category brings together the parts that carry power from the gearbox to the wheels: chains, sprockets, CV axles, driveshafts, U-joints and yokes for motorcycles, ATVs and other vehicles – for repairs and for your next project.

Chain, sprocket or axle – what do the parts do?

Power transmission looks different depending on the vehicle. On a motorcycle, a chain runs over a front and a rear sprocket, while ATVs and cars typically use drive axles with CV joints or a driveshaft. U-joints and yokes connect the shaft to the gearbox and differential, and the boots keep the grease in and the dirt out of the joints.

How to choose a chain and sprockets

The chain must match the pitch of the sprockets and have the correct number of links. BikeMaster, for example, offers 420H chains in lengths from 100 to 130 links, and Renthal offers, for example, a hard-anodised 520 sprocket with 48 teeth for the Kawasaki Ninja ZX-4RR/4R. Choose based on:

• Pitch and width: must match the chain and both the front and rear sprockets.
• Number of teeth: more teeth at the rear typically gives quicker acceleration but a lower top speed.
• Chain length: depends on gearing and wheelbase.
• Master link: clip or rivet type depending on the chain and application.

If you are changing your gearing, a chain and sprocket kit is often the simplest solution, because worn and new parts should not be combined.

Drive axles, U-joints and yokes

On an ATV, a new CV joint can often replace an entire axle – this category includes, for example, joint kits for the Polaris Sportsman and Scrambler. For driveshafts, the choice depends on length, tube diameter, joint type and the power and rpm the shaft has to handle. Measure your existing shaft and check the yoke's spline count and diameter before ordering U-joints or yokes.

Maintenance and signs of wear

A chain typically lasts longer when it is cleaned, lubricated and tensioned according to the manufacturer's instructions. Pointed or hooked teeth, stiff links and a chain that can be lifted away from the rear sprocket are signs that it is time for replacement. On drive axles, clicking at full steering lock can indicate a worn joint, while vibrations at high speed can be caused by worn U-joints or an unbalanced shaft. A cracked CV boot should be replaced quickly, before dirt reaches the joint. Brands in this category also include RK Chain, QuadBoss and Driveshaft Shop.

Frequently asked questions

Should the chain and sprockets be replaced at the same time?

This is typically recommended. A new chain on worn sprockets wears faster, and a worn chain can damage new sprockets. That is why it makes sense to replace the whole set at once, especially if you are also changing the gearing.

How do I find the right chain length?

Count the links on your existing chain or check the manufacturer's data for the vehicle. If you change the number of teeth on the sprockets, you may need more or fewer links. A longer chain can be shortened with a chain tool.

Can I just replace the boot on a drive axle?

Yes, if the joint is not worn and no dirt or water has got in. If the joint clicks or the grease is contaminated, a new joint or a new axle is typically the safest solution.

Does changing the gearing affect the speedometer and road approval?

It can. If the ratio between the front and rear sprockets changes, the speedometer may read incorrectly, depending on where the speed signal is measured. Whether the change requires approval depends on the vehicle and product and should be checked for the specific part number.