Actually, no. The CVT mechanism is incorporated into the engine, which is attached to the frame and is Sprung Weight. In front, the upside down forks minimize un-sprung weight, unlike all other scooters (until the new 2015 Tmax). In the BACK, though, it's still a chain-drive mechanism like your typical scooter. A traditional motorcycle's drive chain has reduced un-sprung weight, compared to that. Oh, and the Tmax from 2012 with belt drive...
Well actually, our CVT is attached to the engine and has the clutch and reduction gear there also, which does not go up and down with the suspension and is therefore un sprung weight.
This system is different then other CVT's which usually have the reduction gearing and many times the clutch at the rear axel, which would tend to increase un sprung weight.
The chain housing has to be heavier as it is part of the suspension, although, because it is one sided it is difficult to determine if it is increasing unsprung weight or not. Enclosing the chain may increase un sprung weight , but, it saves carrying chain oil on a long ride and is well worth doing if only for that reason and it is a lot cleaner. The cover probably adds stiffness to the swing arm.
