[Jared]

Aluminum Gears
We saw little to no wear on all our gears on our final transmission. I'm not sure why the bearing pocket on the dog gears doesn't let the bearing go all the way through. We noticed wear because the bearing and the gear had some slop and could wiggle a little. We got rid of this problem by cutting the dog pockets and a bearing bore that went .250 into the gear so that the bearing was more centered on the gear.

Having the .500 hex in the gear is really useful, as well as the little hub around it that is smaller than the diameter of the inner race of the bearings, which removes the need for a little spacer.

#25 Chain and Sprockets
The aluminum sprockets were surprisingly strong and showed no wear after many hours of practice driving. The #25 chain seems to be a little different from normal chain. The pitch is still .250, but it seems to be a bit stronger, and requires a "Heavy Duty" master link.

Shafts
The .500 aluminum hex shaft is the perfect size to fit into vex pro hex bearings and gears. It's a sloppy fit with the andymark gears and hex bearings, which we measured to be .512. We purchased the longer length of the shaft (maybe 18" ?), and it wasn't at all straight. We ended up not using most of the shaft and just taking the straight sections.

Bearings
They're all very cheap, but the hex bearings aren't as perfect as the round ones. They don't spin as freely, and they aren't all perfectly concentric. Some are a lot better than others. They work, but when possible, we plan on turning down the shaft and using a round bearing so that we can get a tighter fit.

Shifting Dog
We didn't use one this year, but we love the design. The part with the 4-40 threaded hole is thicker, which should make the dog stronger. We didn't use vex pro's dog, and our failure was cracking at the threaded hole.