My seat-of-the-pants dyno could not detect a difference in performance due to less rotating mass. The combined weight of rubber we removed was insignificant in my opinion...even if you multiply it by 6 or 7 as has been suggest previously. Now on the other hand, if you consider how much cleaner the rear skid stays by allowing the snow to pass through the track, I can see where you might make gains due to less rotating mass (ie. less snow to pump through the tunnel). Again, this is only theory, as my dyno can't confirm this. The only thing that I can confirm, however, is that the rear of my sled stays lighter from less snow build up. The skid stays visibly cleaner, and this becomes immediately apparent each and every time I lift the rear of my sled in the morning to free the track. I don't have as much frozen snow and ice to deal with as I used to. Same with when I wash the skid out with the pressure washer. It used to take much more time to free up the snow and ice in the skid. Now there just isn't as much there.
The track is a Camoplast Challenger 162 x 15 x 2-1/2. I drilled 3 holes, each 1-1/4 inches diameter, behind each center lug. I didn't drill in front of each center lug because I thought it might reduce some of the compaction that I think is critical in this area of the track as it spins.
All in all I'm happy with it. The track is standing up just fine and I'd do it again in a heartbeat.
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