First update: Winter commuting. My Marin/Cruzbike is a bust for now. I'll continue learning to ride it when the snow clears
. In other news my Linear now has full studded tires! Had to mod my repairs to get room for the tire in the back, but everything fit nice. Have to run funny air pressures in the tires
20psi in the front, and 45psi in the back. I'm going to see how well 70psi works in the back next.
Now on to the picture below. It's a little toy I hacked together to test belt tracking. With the belt and crowned pulleys from SDP-SI the belt tracks true when the big pulley goes clockwise, and runs a bit off center in the other direction. Also looks like the belt has enough stretch that a fixed idler will be fine. If I add some flex in the right spots it should also be able to shrug off sand and grit.
Now the juicy bits. It's about a 15:1 (81.5/5.5 to be exact) reduction in one stage, and COMPLETELY silent. I could easily use this for the first stage reduction for a 40krpm plus motor. Current plan is to scale it up a bit and use my other motor and a ~20:1 belt to drive my linear. Not sure how long the belt will last, I am pushing it a beyond it's specifications but I'm staying well clear of it's breaking strength. I've got some other belt ideas up my sleeve if I shred this belt. Best of all, I can make my own pulleys for this!