I have a 2009 people s 50 4t, as in 4 stroke. When new, it topped out at an indicated 57-58 kph. Completed the breaking in period and got my first oil change at the dealer. While it was in, I got in contact with Kymco reps via internet. They got in contact with my dealer which proceeded to derestrict the CDI. Result: 68-70 kph. Still, I believe there is still some restriction but I dont care, that speed is good for city trafic. After that, changed the stock rollers. They were 7.0 g., even though the owners manual cites 8.0 g. So, after trying some new 7.0 g rollers, I got some 6.0g rollers. Better acceleration somewhat better up hills, but still, not enough power going up. I mean, pretty steep stuff. I live in a mountain. Did the GPS thing, got 63 kph for an indicated 68-69 kph on the counter. It translates as 39 mph. There was no restrictor on the variator. I tried removing the restrictor in the air filter, but the engine cant take it with the stock jet. It just starves for fuel as there is to much air coming in. I think the last remaining thing left to be done is getting a .85 main jet in the thing and opening up the air intake. As I said, I dont need more speed, just more climbing power. Funny thing though, acceleration seems adequate, never seems to slow down traffic, as a matter of fact, usually the contrary. But the minute I encounter a slight incline, it slows down to 50-55 kph, slower on steeper ones. I'm just lazy about the carb and my wife, which is much lighter than I am ( I'm 200 lbs) doesnt seem to complain. My real bike is a Suzuki DL 650. But still, scooters are so much fun around town....
All this might help you, since the mechanicals on the People s50 4t are about the same as your Super 8 4T. I wouldn't change the variator, I believe It will not give more performance, maybe smoother performance, but I find it acceptable on the Kymco stock one. What I havent figured out is if changing the big pring in the rear part of the trans mission will allow the engine to raise its revs when in need of more power going up hills. As it is right now, it just seems to settle at a constant rpm and just slow down to about 35 kph on the steepest of hills and just stay there until the incline levels off, then the needle on the speedo just sweeps up again.
All in all, maybe not the most performing little machine, but up to now, a very reliable one and easy to drive. Also very cheap on gas.