Thunder Shift TRA Pin Kits
Superior Performance Through Superior Clutching

Get Weight Specific Clutching by installing the TRA Thunder Shift Pin Kit
 in your Ski-Doo clutch.  This means you can adjust the performance of
 your clutches to the specific weight of the rider and sled combination. 
Up until now, tuning the TRA clutch to Weight Specific Clutching has been
 difficult at best.  The Thunder Shift Pin Kit for the TRA is specifically
designed to give you that performance edge.  Works in conjunction with
your stock weight arms or, for more precise control and wider adjustability,
combine this kit with the other TRA products we offer like our Thunder Shift
 adjustable arms or oversize rollers.

WEIGHT SPECIFIC CLUTCHING
Whether you have been around snowmobiling many years or just a few, you have probably realized that the most "bang for the buck" in terms of performance comes from proper clutching. We want to introduce you to a new term called Weight Specific Clutching. In a nutshell, this means a specific rider and sled combination require a specific amount of weight in a clutch.

Lets say we have a 500 pound sled with a 100 HP engine. If the rider's weight is 200 pounds, that is a total of 700 pounds or 1 HP for every 7 pounds of weight. now lets say we have the same sled with a 130 pound rider on board. That is a 70 pound weight advantage or the equivalent of a 10 HP advantage. What we are getting at is that weight equals horse power. Even a 7 pound difference in rider weight is the equivalent of a 1 HP advantage. Every change in HP requires different clutching. Nobody argues this!

Very little consideration or effort is given to clutching a sled differently because of a 20, 30, 40, or even 50 pound weight difference, although it is the same as a HP difference. The reason this is not talked about or given much consideration is because this has been a difficult task, often involving different weights, primary springs, secondary springs, helix, or even worse, having to grind the clutch weights or ramps by hand in a hit or miss fashion. Now you can easily practice weight specific clutching and get that fine performance edge usually reserved for factory riders. The Thunder Shift clutch kit was designed with WSC in mind.

The bottom line is this: if you throw all the weight at your engine that is possible without the RPM's dropping below the desired RPM and your sled holds this all the way to top speed that is the fastest that your sled can possibly run regardless of who clutches it. That is WSC!!

TSK-190 - Ski-Doo Thunder Shift Pin Kit (3 grams to 19 grams)    $59.95

Customers Who Bought This Item Also Bought:

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Thunder Shift Rollers - Made of the finest material and meet or exceed all OEM specs for a fraction of the OEM price.

Glide Washers - Stop your spring from gouging into your clutch cover and spyder

Ski-Doo Secondary Springs - Absolutely the best spring you can buy without spending over $100.00