Replacement Belt for American Educational 7-511 Van De Graaff *Belt ONLY

I've had the American Educational 7-511 Van De Graaff generator for about a year and a half. I knew that when the machine is stored that the belt should be removed, stored in a sealed bag and out of the light so that the rubber doesn't break down, but I didn't do that. I took it out of storage a few months ago and it didn't work. I took it apart and cleaned everything and it worked great for about 15 minutes. Then it quit working. I cleaned everything again and it still did nothing. I couldn't figure out why. Finally, I tried making a new belt out of some exercise bands and it worked, but maybe only 10% intensity. I Found out that they finally made the belts for this machine available on Amazon, ordered a belt and my VDG works like new again. After maybe half an hour of use, the intensity drops and I rinse the lint of the belt with some distilled water, let it dry and it's back to 100% again (and I store the belt in a Ziploc bag in the dark when it's not in use). In the instructions that came with the belt, they recommend using some light grease on the axle for the upper roller. I tried this twice (without getting grease anywhere else on the machine) and the machine quit generating sparks. Once I cleaned the grease off, it was back to working again. The axle for the upper roller does get slightly warm without grease but the roller doesn't seem to be wearing out, so I think I'll leave it dry.

Don't you just hate it when your Van de Graaff stops producing those big impressive sparks? I adjusted and cleaned everything (including the old belt) but no joy. Replaced the belt with this one and the sparks are flying again! BTW, I have the exact model generator that this is listed for - probable won't work for any other models.