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I would like to get some feedback from some people with shock mounting experience. While going to college I worked on the suspension team for a SCCA scale formula car. We dealt alot in suspension geometrty. roll centers and "unsprung mass". I am questioning the later of those. For those who don't know "unsprung mass" is the mass of the suspension, wheels (ski's, upright and shock in our case) or tracks (as applicable), and other components directly connected to them, rather than supported by the suspension. Intern unsprung mass is the ammount of mass the spring and shock have to move to keep the ski's on the ground at all times. It would lead us to believe we would want to reduce this as much as possible to. This will allow the suspension to be more responsive in rough terrain. This is one of the reasons why Indy cars have the shocks mounted imboard (this also helps for aerodynamics at 200+ mph). I have notice on most sleds including mine, the shock body and spring support are mounted to the upright end. Wouldn't it make more sense to flip the shocks around. This would reduce the unsprung mass at the ski by several pounds (depending on the shock style). Does anyone have any thoughts on this. Does anyone know why Arctic Cat didn't change this. Maybe on a snowmobile everything is different.

THOUGHT?!?!
 

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I'm a mechanical engineer and used to crew chief a professional race team. I know exactly what you mean by unsprung mass. As for the shocks, the mass of the housing vs. the shaft and piston are pretty close as the housing is aluminum with a somewhat thin wall. The advantage of running them in the inverted position would be minimal. The main disadvantage would be that all the crap and spray from the skis would damage the shafts much faster. The same reason they don't run them inverted on automobiles and off-road trucks and buggies. If you were oval ice racing it might be beneficial to invest in hollow shafts and run them inverted.
 

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Some models come from the factory with the shock body to the top. These models are the highest performance models and sleds with remote reservoir shocks. The remote reservoir mounts to the "wheel well" and you want the minimal movement on the hose connections from the shock body to the remote reservoir. The spring and damper don't care which end is up. It is less unsprung weight with the shock body to the top, but the shock rod is subjected to riskier exposure in that orientation. The choice is yours.
 
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