I put a Hoca variator with 14 gram rollers and it rocks to 65 MPH with good take off and a pleasant midrange.
When I opened the CVT to inspect it, I found the 13 gram rollers were a little flat spotted after 5000 miles. The RPMs were kinda high stock,so I put 3 14s and 3 13s, and it was better, so I put 6 14s, and it's better still. I'll try 3 15s and 3 14s to bring down the RPMs a little more, but if it starts to sag,I'll know it's too heavy.
The Hoca is a high performance GY6 variator for the Chinese scoots but it fits and runs great, and I know the Koso will work, too. My stock variator was grooved a little, and it's a lot heavier, but not any bigger than 115 mm.
I just got a used variator from an Agility 125, and it is identical to the stock Super 8, and even came with 14 gram rollers. It's more worn than mine, but it came complete with the boss and the plate and the nut, so I can't complain for $30. I think it was run with a belt that was too short, the groove is worn almost a half inch from the edge, so it never made it out to top end.
You might just try some different 18x14 roller weights that you can get from Scooter Assassins in Taiwan, Carlos is an awesome dude, he'll help you out, and if you need anyone assassinated, well, let's just say he's an awesome dude.
He was out of the correct belt last month, and I bought an 821 20 30 from Hong Kong that I think will work, if not, Carlos will get one for like $25.
