Thanks for the kind words Mark, Jim and Danny.
I'll throw some thoughts out on the different weights. First think of the weight as an object that pivots on a fulcrum point. At initial engagement the gross amount of weight is the predominant force and the location of the mass is less a factor. As the clutch shifts out the mass location is very important because of the amount of leverage it exerts-more tip weight more leverage...less tip weight less leverage. Most Polaris weights have the same profile (curve), but changing the profile has an effect on clutch shift too. Too many variables and tuning your clutch gets way too complicated for most.
There is no weight that's best, it's more of getting one that fits the torque curve of the engine and sync's with the driven setup. To make this more complicated the primary springs have different preloads (engagement pressure) and different finish rates (full shift). Generally it's better to run a stiffer primary spring and heavier weights. The more weight in the primary, the less "fickle" the clutching will be in different snow conditions and at different altitudes. In other words your sled will work better over a wider range of conditions.
The 11 series Polaris was developed for the big torque 900's. The 10's are used on most other Poo's.
The Belly Buster weight is a duplicate of the Polaris 10 series at 66 grams and above. For that reason there is no reason to buy a more expensive BB if you run 66's or greater. For at least 2 years the BB's come with a bushing that is larger than the Polaris bushing. This does 2 things; First-belt side clearance increases so you should reduce belt side clearance if you are going to run BB's. The P-85 has way too much belt side clearance anyway so that's a change that everyone should make to their sled. This is not a warranty item so it's on your dime. Polaris probably left them wide for the 1080 belts that is .022" wider than the 1115 belt.
Second, the oversize bushing on the BB's lets the weight slop from side to side more than it should. This will result in the weight tip hitting the spider sooner with BB's than with weights with the correct size bushing...not a big deal but something to keep in mind. Last year the BB's I weighed were inconsistant, varied too much in a set. I bought a set of 62's in 08 that weighed 62. In 09 the 64's were closer to 66's and had almost 1.5 grams difference between the lightest and the heaviest. this has always been true of Polaris weights, just not what you expect from a custom weight.
SLP MTX weights have holes and rivets that allow changing the amount of weight and the location of the weight mass. These appear to be very flexible but are not easy for the average sledder. SLP provides a guide so you have a starting point, but still must understand what you are doing and normally make changes at home. There are several other adjustable weights available each with pros and cons. In a way adjustablity is good, but it just doesn't work for everybody.
When you put all the combinations of driven clutch and drive clutch combinations together, clutch tuning is not for the average Joe.
