The VPI Rim Drive

The $64 question with VPI rim drive is whether the rubber belts between motors and flywheel compromise speed stability. If you're in the mood to experiment, you might try carpet thread in these positions. On my TNT there were improvements in the direction that you note-- focus, speed, dynamics-- after replacing both long & short rubber belts with inelastic thread. Rim drive should be even better, but perhaps not with elastic belts remaining in the drive system.

Stringreen,

Did Harry mention what led him to reject alternatives to the two remaining rubber belts? IME the only advantage of soft rubber belts is ease of set-up-- and ease of set-up and consistency of results is a big consideration when you're a large manufacturer. I'm still hoping that someone with VPI rim drive will try threads(which are tricky to tension correctly) and report to this forum. I would be surprised if you don't hear an improvement.