Great information- - and also wondered why go with a kit that adds a tensioner when I did guess (as you stated) for a piece of mind- but come with a price also.
Do all the MFG's you listed have the billet sprockets? as running 8,000' to 10,000' Me thinks gear change is going to be necessary especially running a 163---- Whats your thoughts on that???-
No tree hunting just good ole fashion boondockin and climbing-- . Cannot afford the tree carnage..LOL
S/C
1) The tensioner allows you have a greater range of Gear ratios available to you. With the fixed center to center distance of the shafts, it would be similar to what cat was regulated to with the DD, about half dozen ratios at the most and every one a complete new set of gears (which becomes very expensive fast). By paying for the tensioner up front, on most belt drives you only have to buy one extra sprocket per additional ratio which makes it a far cheaper option.
2) Yes, all the vendors I listed, the sprockets are machined from billet aluminum. Likely a vast percentage are actually machined by 2-3 shops as Gates is quite particular who it licenses it's tooth profile tooling to. (Gates does cast sprockets for their industrial line but they are cast steel and cast iron and the tooth profile is still machined not cast as in the stock QD stuff.)
3) I'm at sea level and I gear all my mountain sleds for 75-80 MPH, (acceleration junkie) this comes from my racing days when I learned that it was counterproductive to gear any higher than the speed the sled could achieve between the gates. As the maximum efficiency is when the clutch is at full shift and a 1:1 ratio, maximizing contact and power transfer and the least amount of parasitic loss. Even at altitude that ratio should serve you well. But as I mentioned in #1 ratios are cheap if you want to try a little either side of your starting ratio.
I would rather tweak the clutching at that point. if you have a well balanced clutch setup it should just need a weight change for altitude. If you over spring it and have a lot of helix in your secondary, your clutches will be fighting each other regardless of altitude and you are losing responsiveness and efficiency. Most modern clutch setups are fundamentally wrong, and are handicapping themselves, IMO. That is why you always hear someone changing helixes because they could not make the target RPM. The regulation of RPM is a sole function of primary spring and clutch weight. The secondary's sole function is to keep the belt tight enough to not slip and to sense torque and react accordingly.
I hope I explained that well enough, but again just my thoughts, as you asked for them.
MountainHorse; I just noticed that we are off topic: If you'd prefer to relocate this portion of the discussion, if should it continue to develop. Rather than perpetuate the derail. Your call.
