[IsaacCarlson]

Yeah, the mass marketed beads are very expensive, and messy. That's why I went with airsoft bb's. The steel bb's I tried first worked for a while, but finally wore down to double ended thingys, not sure what to call them.

At low speed the bb's are against the tire, but still roll down a bit as they go uphill in the tire and then roll back down a bit as they go downhill, and they do this on every revolution of the tire, until you go fast enough to get them to stay in place.