Started up the saw today and there was a distinct sound of belt squealing. I checked for something obstructing the blade, found some narrow cutoffs down inside that I pulled out, started it up, still squeal.
Checked the belt--it was horribly loose. It's tensioned by the weight of the motor and a small spring, and the motor was at the limit of its travel, so my first reaction was "holy crap, I need a new belt". Looked closer and found a couple of rods held in place by set screws that rough-positioned the motor. Pulled on the motor and it slid right out--the set screws weren't tight. Slid it until the motor was at about the center of its travel and tightened the set screws and fired it up, and not only was there no squeal, but it spun up a lot faster and cut a bit cleaner--I guess I missed a step in the setup when I originally put it together.
I figured I ought to mention it just in case somebody else with one missed the same step.