— Continuously Variable Transmissions (CVT) are wonderful things, as they help deliver engine power to the drivetrain and automatically vary final drive ratios. CVTs have primary and secondary clutches and variable-diameter sheaves connected by a belt. Basically, as the primary clutch gains revs, it expands with centrifugal force, which causes the belt to act on the secondary clutch and force the sheaves apart. It’s like replacing a large rear sprocket with continuously smaller ones through the rev range for more top speed. The spring-loaded secondary uses a combination of plastic rollers and sliders to facilitate the expansion and contraction of the two sheaves, which, over time, can gall the sheave faces. Also, dirt wears the plastic sliders and can eventually damage the secondary housing, causing the rollers to flat-spot. A sticking secondary blows belts.
On our 2015–2017 Polaris RZR XP 1000s, the sliders (#3514926) are 28 x 13.5mm and the rollers (#3514929) are 9.58 x 28.83 x 13.97mm. Inspection of our 2015 XP1K showed galling and roller wear, so we set out to rebuild and upgrade the secondary. This procedure will also apply to those installing a CVT clutch kit with a different secondary spring.
Polaris sliders and rollers are $25 to $30 apiece, so Hunterworks made a replacement kit with high-grade exotic plastic that is impregnated with a substance that is five times slicker than Teflon. The rollers have tighter tolerances than the injection-molded stock rollers, which are loose on the shaft. They’re tested to 400 degrees with no deformation and CNC-manufactured in the USA.
Prices are $60 for the secondary roller kit and $65 for the 2016–2017 secondary roller conversion kit. Both have four high-lubricity rollers and pins, enough for two rebuilds.
WARNING: Much of the action depicted in this magazine is potentially dangerous. Virtually all of the riders seen in our photos are experienced experts or professionals. Do not attempt to duplicate any stunts that are beyond your own capabilities. Always wear the appropriate safety gear.
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