Hypershift Clutch Kit

How do you make an already fast sled even faster? One of the most cost effective methods is to install a clutch kit. There are many capable clutch kits, and the right one for you many times depends on your riding style and conditions more than anything else.

We installed a “Hypershift” Clutch Kit offered by Hot Seat Performance into our XC 600 SP VES EDGE and were quite pleased with the improvement in acceleration, as well as a responsive backshift, making this clutch kit well suited for a wide range of conditions.

Precision gram-matched notched flyweights and a new primary spring raise the engagement RPM, and a smooth shifting Teflon-coated multi-angle helix with a new secondary spring provide a good backshift response and allow the secondary to quickly upshift for impressive power transfer. The Hot Seat Kit pulled down the operating rpm of the power valve 600 twin right down to about 8000 RPM, while the stock set-up spun a bit higher at about 8200 RPM.

We also tested the Hypershift kit on the SnowTech SLEDyno that measures track horsepower and backshift characteristics. The track dyno is simply a method by which we can attempt to better quantify performance that we experience in the real world.

Compared to the stock calibration, the Hot Seat kit transfers more power to the track all the way through the acceleration sequence. While the stock clutching set-up produced 59.7 track horsepower, the Hot Seat Hypershift kit produced an impressive 64.9 track horsepower. (At about 90 mph we lost positive power transfer, and any data past that speed is meaningless.)

Track horsepower graphs that only show the track horsepower (upshift characteristics) can be misleading, as there is the other side of the clutching equation; the backshift. If you do any type of riding other than straight-line racing, the backshift response is an important piece to the total performance each set-up provides.

During the backshift testing, both the stock clutching and the Hypershift kit exhibited a similar loss in engine rpm as well as recovery response times, indicating the Hypershift kit was backshifting very similar to the stock calibration. Right at about the 1.8 second timeline you can see how the stock calibration lost a few RPM, and at the 1.3 second mark the Hot Seat Kit also dropped some rpm. What we’re looking at is how many RPM were lost, not the exact time which it occurred (which is a function of when we applied the dyno brake). Both kits lost similar RPM when the brake was applied.

The second part of our backshift test involves “response time”. If we let the engine rpm drop and full-throttle is applied, how quickly does the system recover to full rpm under load? Full-throttle was applied to the stock set-up at 3.7 seconds, and it recovered at about 4.5-4.6 seconds, indicating a recovery time of about 0.8-0.9 seconds. Not bad. The Hypershift kit recovery started at about 3.75 seconds, and was back to full rpm at about 4.6 seconds, very similar in recovery time (0.85 seconds). Like we discovered in the field, the Hypershift kit provided improved acceleration and a responsive backshift.

Hot Seat includes several extra tuning components in their kits, including metal shims to adjust the starting angle of the helix and nylon shims to adjust belt-to-sheave clearance in the primary. Hypershift clutch kits sell for $189, and are available for most Polaris models. Contact Hot Seat Performance at 651-982-0600 or visit www.hotseatperformance.com