Rotating Mass

[RIVERRUNNER]

I have a question on how much rotating mass really affects speed. I just changed out my track from 192 studded, one inch, fully clipped, kimpex aggressor track to an 1.25 ripsaw that is clipped every 3rd window. I weighed the kimpex and it was 64 pounds. My ripsaw is weighed and 36 pounds on the camoplast website. If there is a change in speed, where am I going to notice it the most? I know last year my top speed on the speedo on a lake with little snow was 114. How much of a gain will I see by losing 28 pounds of rotating mass? Furthermore, is a pound of rotating mass noticeable? Like drilling out your brake rotor? Thanks guys this is the best snowmobiling site out there!!!!!!!!!!!!!!!!!

 

[2ooosrx]

Rotational mass has a squared affect with the diameter of the object that is rotating. This means that the larger the diameter of the object that is rotating, the larger effect on performance gains or losses. Nothing rotating on a snowmobile is larger then the track so by lossing that much weight out of a track, there are going to be considerable gains of performance. You will notice increases throughout your entire run (bottom, middle, and top speed). Another thing to throw into the equation is the wind resistance of a track. The ripsaw is going to have a great wind resistance then the kimplex which should only effect you on top speed. However, because so much rotating weight was taken out of the track, you should still experience higher top speeds even with the ripsaws higher wind resistance. As far as drilling a rotor, there are going to be gains, but nothing that you should be able to feel on a sled. These gains may show up on paper, but you probably will not feel any change. Drilling rotors and things of that nature may be orientated to the drag racer type rider or someone who wants every possible advantage to beating his buddy. Hope this helps