AmSnow.com is now SnoWest.com
Still not idealDespite all this progress, the roll center situation is still not ideal, compared to a car.
While we can manipulate the roll center location in the front, we have no such tools for the rear.
People often ask me where the roll center is on the rear suspension. Sad to say, it's still down on the ground somewhere around the outside slide rail, depending on the stiffness of your track.
It will likely stay there until we have some kind of twin track vehicle with independent linkage suspension, but I doubt we'll see this in the near future.
Twin tracks of this design were built back in the 1970s for oval racing, but never caught on. I believe the single-track snowmobile with two skis will be the preferred mode of winter fun for a long time to come.
With the roll center still on the ground in the rear, the roll axis slopes upward to the front.
A saving grace in the back is that there's no heavy engine mass trying to roll the sled around the low roll center of the rear suspension.
Actually, the opposite is the case, because the main mass in the rear is the driver, and he uses his body weight to counteract any roll by leaning inward in corners.
Moving the driver forward has moved him a little closer to the roll axis but it's still debatable if this has hurt his leverage in the turns, because the seat position also has moved up at the same time.
Although the situation at the front is greatly improved, the low center at the rear means we probably still have to use some "body English" on the trail.
But hey, who's complaining. A little roll gives the driver a good feel for the sled, and it's also part of the fun of snowmobiling.