I think the OP was talking about a video I did testing the top speed of one of the belt drives that I made. I really don't think the spindles should run at 9000 RPM because they do make a fair amount of vibration at that speed and if something broke loose at that speed it really could be bad.

The video is here. 9000 RPM Test - YouTube

I posted a good amount of pictures here. arizonavideo's's Library | Photobucket