Production of the Yamaha RZ350 began in 1983. This was Yamahas follow up to the RD LC models. The RZ350 came with YPVS (Yamaha Power Valve System) making this bike extremely quick. The RZ is a lightweight motorcylce with alot of torque and superior handling ability, making them a popular choice amongst racers, including the "King" Kenny Roberts.
A Big Thank you to Jay Mendoza for the following information