canadian offers rad suspension

After many years of designing and testing prototypes, Canadian inventor Shawn Watling is unveiling his patented RAD (Rear Axle Drive) suspension.
On his new suspension, the rear axle drives the track. The track is part of a rear suspension arm controlled by shocks mounted to the tunnel. The rear shock mounts are controlled by an electric motor and can be adjusted on the run to alter ski pressure.
The track enters the front of the suspension via a large idler wheel, and allows the longer flat track surface to be under tension as it slides across the snow. Because the track does not have to go all the way up to a front drive sprocket, a 121-inch track will have the same surface on the ground as a 151-inch track on a conventional suspension.
This also allows the total track surface to be closer to the skis for much improved flotation in deep snow. The slide-rail portion, including the front idler, pivots around the main support rail close to the rear axle and movement is controlled by an additional front shock.
A knee-action joint in the front makes sure the slide-rail frame is kept securely in position as it pivots in relation to the main swing arm. With the drive force through the chain going parallel with the main swing arm, there is no torque reaction being fed into the chassis. This means a flat ride with minimal ski lift.
The result could be a safer ride under hard acceleration, as too much ski lift is a problem on long-travel rear suspensions. Since ski pressure can be adjusted on the fly, a nice feature is that you can lift the carbides as you cross roads and parking lots.
Shawn claims its lighter weight since a 121-inch track performs the same as a 151, while it leaves the chassis shorter. With a footprint position closer to the center of gravity, the sled also turns easier in deep snow.
The large front idler wheels compact the snow better and help pull the sled up on top of the snow. There are a number of promising features in this design, and AmSnow test-ride guru Mark Boncher is looking forward to putting one through its paces this winter. For a full set of key features from owner Shawn Watling, updates, tech info, videos and more on the RAD Technology tune into www.amsnow.com or www.rndinnovators.com.
- Olav Aaen