All CVT transmissions scrub power, They are not efficient, Those who have sled background and knowledge know how temperamental dialing these in are and with changing elevations its a moving target, Not to mention all the weight , With limited HP it will not pace with a properly geared bike..
I see this "CVTs are terribly inefficient" argument posted quite often, however, I still don't understand it. I have over a decade of sled background and knowledge, including dialing in clutches on 10+ sleds...sure it takes a lot of time and can be annoying, but once you do get clutching dialed in the results are always satisfying.
I've seen data & arguments for manual gearboxes being 95-99% efficient, and CVTs being anywhere from 65-85% efficient. These were measures of efficiency as either HP to the ground or fuel economy, and were at a single constant speed. At a single constant speed, a gearbox is always better than a CVT, sure. However, engines do not generate the same efficiency at all speeds or rpms (not even close, in fact). And we do not ride at a single constant speed. The benefit of the CVT is that it can vary the engine rpm as needed to access maximum power regardless of current vehicle speed or load conditions. And so, in variable load conditions, the CVT dominates by keeping the engine close to its peak power RPM at all times. This is true even before we factor in the drag and delay associated with each manual shift.
Snowmobiles/snowbikes experience a wider range of variable load conditions than any other powersport I can think of...and so, on snow the CVT persists as a transmission worthy of consideration.
And for the record, that's not to say CVTs are perfect. I believe there are also strong arguments for the following downsides of CVTs:
- the added weight and rotating mass
- they make your entire engine & drivetrain much wider
- they require tuning to setup, some maintenance, and periodic belt replacement
Further reading for anyone who is bored:
Olav AAEN's clutch tuning handbook - see PG 5 and PG 9
https://vdocuments.site/clutch-tuning-handbook-olav-aaen-1979.html
Visual graphs explaining the power delivery difference
https://ieee.nitk.ac.in/blog/cvt/
CVT
https://pdfs.semanticscholar.org/e483/9fd5c623ddec048da326d861395bc66041d8.pdf
Other discussion about CVT efficiency on snow
https://www.dootalk.com/forums/topic/341004-cvt-vs-geared-transmission/