VPI motor - upgrade to 300 rpm?

Today I got this reply from Mike at VPI:
"The 300 RPM motor does not work on the HW-19 so that is not an issue. The 600 RPm motor should work perfectly when you get the capacitor right for your countries voltage and frequency, it is a critical item and if you are willing to play with different values you can fine tune the motor for lowest noise and running smoothness. Mike"
No use running after a 300 rpm motor, then. Capacitors, here we come. Has anyone tried?
Storyboy, this sounds very interesting, can you explain a bit more ("in front of the pulley and tensions the belt around the pulley 180 degrees")?
Amazing what one can achieve with further improvements like these...

I posted a pic, just follow the link .

The brass flywheel comes from an HO scale model train motor, and the rest is rigged. It works.

http://trade.audioasylum.com/ca/wtb/listing/Turntables/VPI/Scout/pulley/43555

Storyboy, thanks a lot, it looks very effective. For now I am testing threads, one silk, one nylon, both ca 1mm thick. I can tension the thread by adjusting the player feet to widen the distance to the pulley. The platter starts ok and I do notice sound improvements, but I have not managed to get the speed right. Since it had been used with the standard rubber belt, the SDS was tuned to 72 volts / 60.00 hz (for 33 rpm). With the thread it remained too slow even when I turned it up all the way to 66.00 hz, which is the top level for 33 rpm. I tried switching to 45 rpm, but then it went too fast, and remained too fast even when turning the hz fully down. My pulley has two groves, one small-diameter at the top which is correct for the rubber belt, and one larger below it. I tried changing to the larger grove, but this made the speed even faster and did not solve my problem. My experiences were similar with the two threads. I also felt that the speed was a bit fluctuating, but I must get it fairly right before I can tell. Advice welcome.

I had a problem with the big rock and got rid of it. I have a TNT Jr. And found temperature changes were effecting the sand in the big rock, and throwing off leveling, effecting a few things. Vpi on my Billy bags rack now and improvement was significant. I have a small custom svelte shelf under the motor.

Wow, made it with the nylon string! Turns out I had to use more tension, and a double knot (with the knot at the outside of the span). The nylon thread/string creates very interesting sonic changes, the whole thing seem to be clearer the bass more distinct. So thanks a lot for advice, and I will follow up on the other suggestions too.