wondering if it could keep me at 55. By the way I'm just a little guy of 320#.
At 320lbs....55mph?
You would be riding constanly with the throttle jammed to the stop.
Not a good way to drive a car, nor a scooter.
Also, the short wheelbase and light weight of this scooter would not give you a stable or reassuring ride at that speed, especially when trucks pass you!!.
You would need to give the seat a thorough rebuild to add more padding (the seat of this scooter is a major complaint of many owners)
I think you need to step up in scooter size...in the Kymco line, or test a SYM 200 at the very least.
You will most likely regret your purchase if you buy too small a scooter. If you get the correct size...it will be a blast to ride & own!
Stig