Well of course it would. I don't know the approach angle to calc exactly, but just using 45* as a value (135* of contact) you would only have 2.25 teeth engaged at a time.
A 7 tooth driver on the other hand would have 2.625 teeth engaged.
So the amount of time that the track is out of contact with 3 full teeth is:
75% of the time for the 6 tooth
and
37% of the time for the 7 tooth.
To go with a smaller driver for the sake of air pumping - and sacrificing driver contact seems like a poor equazsion to me. If you were a lake racer - sure, but you're never gunna bring a full paddle's worth of snow on up and over the back axle, and what track speed doo you carry at best? 50mph up the hill? 60 on the outside? (I really don't know as I am in need of a newer machine)
Sure - there is air moving through there, but I doubt that you would ever see much "pressure". Just volume...
Aren't the tracks on the 850's a 3.5" pitch? (not that it changes the math) But that get's to be a large driver....
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