I’ve finally started bolting together my second electromagnet testing platform. This is built on an MDF base, attached to an old Elite Chrono Fluid trainer stand.
For the roller I’m just using an old dumbbell shaft, held in a couple of one inch pillow block bearings. Shaft collars hold the flywheel weights, and will also hold the brake disk once it’s added.
A first spin up with the bike has highlighted a lot of drag in the bearings, despite some attention with a grease gun. You get what you pay for I suppose, and these particular bearings were pretty cheap and agricultural. The drag might not be noticeable on a tractor, but in this configuration my PowerTap says it’s taking over 400 watts just to hold a steady 20 kph!
Hopefully this is just drag from the seals, so next I’ll pop those out and try it again…