If you’ve been reading the recent news releases on Polaris’ new Pro-RMK 155 mountain sled you may not have realized this sled has some very ground-breaking new technology.
The top headline is its incredible reduction in weight – the engineers have gotten the sled’s mass down to 417 lbs, dry.
Pretty impressive to say the least, and it makes this sled the lightest in its class by a considerable margin.
However, we think even bigger news is its use of a rubber belt drive in lieu of a chaincase to transfer power to the track.
This is a pretty big development considering nearly every snowmobile for decades has used a “wet” chaincase with heavy gears, tensioners, drive chains and castings to get the power transferred from the jackshaft down to the drive axle.
Without question the belt system is way lighter and long-term engineering and testing on motorcycles has proven a belt can be just as reliable as a chain in this application.
Naturally, our minds are exploding with the possibilities of this tech being used on more sleds in the future.
We spoke to some engineers and they told us the main problem with using it on existing sled platforms is space in the right footwell. Due to the placement of the large bottom pulley there are limitations with current design layouts, especially when different gear sets (pulleys) need to be employed.
Nevertheless, we think this technology is highly valid and could be put into play as new platforms are brought out.
We’re not sure who actually owns patents on this idea but it’s a good one and the massive weight reduction to be gained makes it pretty tempting for use as a drive system on all sleds.