Mike, I took the doo belt off when the sled was brand new so I have no good idea on how the belts compare RPM wise.
I got out and rode corona pass this past weekend, some new snow which made the conditions ok, but nothing special. This january has been horrible for snow in CO with no snow in sight yet in the long range forecast.
I got to ride with a timbersled snowbike today, and even got to take it for a spin. First time riding one. I will say it is much different than sledding and I think def has its place on the mtn. However I will be sticking to machines with 2 skis for the foreseeable future.
No real update on the T-3, I changed the chaincase oil this past week and adjusted the chain tension, also loosened the track as it seemed kinda tight, was hoping to free up some potential HP. However the track would ratchet on the drivers when pinned at real slow speeds, so I will have to tighten that back up this week.
Also to answer a question above, I run Texas Tea for oil in my sled, found here.
http://www.amazon.com/TEXAS-TEA-2-S...&qid=1422290912&sr=8-5&keywords=texas+tea+oil
The only reason I run this, is cause it is the cheapest decent looking oil I can find. Its cost about 28$ a gallon right now shipped to your door. And by decent looking oil I mean I really no little about oil, but have a hunch this stuff is will not make my engine blow. To me its not worth spending 40$+ a gallon on other brands. Its smell is pretty odorless compared to the XPS.