Adjustable Weight Kit for the 850 Ski-Doo pDrive
The 902 Pro Tuner Kit from Dalton Industries is a fully adjustable weight kit for the Ski-Doo 850 sleds with the adjustable clicker-style pDrive primary clutch.
Most low elevation 129-137” 850 Ski-Doo models have 49g stock weights. The 902 Pro Tuner Kit comes with 48 gram base weights that can be loaded up to 55.7 grams and are designed for use with the stock clicker assembly. The stock pivot bolt can be used or there are other optional ones from BRP (or aftermarket) to allow for even further flexibility. The top profile of the 902 Pro Tuner flyweights is similar to the stock BRP #968 ramp curve on these models.
The weight adjustment is done from the side of the flyweight. There are two threaded holes available to allow the position of mass to be placed in the in-bound or tip position. While many racers and tuners prefer the Dalton “Quick Adjust” type of weights, for this application this configuration allows for more control of weight placement to best suit the application.
There are many combinations of added fasteners that will allow the fine adjustment of “total grams”, as well as the different placement locations. Many combinations of less than one gram increments can be done in different configurations of weight placement on the flyweight. The threaded holes all have a bottom, so that even the set screw type fasteners bottom out secure. Everything needed for the included gram increments listed is in the package.
As the name suggests, this Pro Tuner Kit was designed to help satisfy requests from clutch kit companies, pro racers, and performance shops who want to tune their own clutching to suit their own needs and/or performance levels. Therefore, Dalton does not offer a set-up guide for specific models or applications.
That said, many users of this kit seem to end up in the 51-54g range (not including the pivot bolt) for many of the 129-137 models, and there are many variations. Things like gearing, clicker position, different helixes, springs, pivot bolts and other components all work together as part of the recipe. Not to mention engine /pipe mods, traction or tracks and terrain applications.
Many times you will receive this kit as part of a package from, or on the recommended weight grams from a speed shop or provider of performance mods. They may have recommended settings for you if they have experience with your specific application.
Again, this is very clearly a “TUNER” kit for experienced clutch tuning professionals with proper tools, tuning knowledge, and assembly specifications for the pDrive clutch. It retails for $269 CDN or $225 USD. Contact Dalton Industries or
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