There haven’t been too many advancements in the last 25 years. For all the fancy looking stuff it’s still just a steel tube frame and 4 rubber tires. For $600 if it has good brakes buy it and put a new graphics kit on it.
FAA certified jet engine and aircraft technician,
Nicholson Speedway class champion 2001,
Yamaha KT100 Service Center,
41 years karting experience