Yamaha Scooters: Worth Modifying For Better Performance?

By Author: drowsports
Total Articles: 13
Comment this article

The Yamaha Zuma is a modern, sleek 50cc engine that cranks out plenty of power. With it telescopic front fork, fat tires and rugged attitude, the Zuma is fuel efficient and designed for scooter enthusiasts to cruise around for years to come says Honda Ruckus parts designer.

The majority of 50cc scooters and many bigger scooters have 2-stroke (also "2-cycle") engines. These have higher output than 4-stroke / 4-cycle engines (as found in most cars) however they are difficult to keep running as efficiently. When it is a 50cc scooter, overall efficiency is still much higher if you consider that an engine around 40 times smaller than a car's is moving one person around. The parts such as Malossi cylinder kit and other parts are made of materials similar to other motorcycle/car engines, and a typical Japanese 2-stroke 50cc will rev to 8.000rpm under normal use. The main zuma parts and systems are similar, they need air cleaners, a device for mixing air and fuel, the combustion engine itself, and an exhaust and muffling system.

2-Strokes:Two stroke engines generally produce more power than four stroke engines because ...
... they provide twice as many power strokes at a given rpm. They are less efficient so the output figure is usually not exactly twice that of a four stroke. 
Two stroke engines are simpler in design, not having moving valves, cams or oil sump systems. Sports/racing tuning of a two stroke engine is based around the ports and exhaust. So if you want to get more performance, look at your exhaust first. According toStage6 cylinder kit manufacturer, performance exhaust for a 2-stroke engine use expansion chambers. This allows exhaust to expand in the optimum volume as it cools and exits towards atmospheric pressure. Well-designed chambers supposedly use sonic waves reflecting from the reducing conical areas to aid scavenging and help to stop intake charges escaping through the open exhaust port. A two-stroke chamber's shape is something like a long cone with different, calculated steps where the cone gets bigger to form the chamber. The cones angles affect the power band width and amplitude. These cones form primary and secondary chambers and are unique for each engine, depending on port shapes and exit velocities. Timing of scavenging of the exhaust pulses is important to create power. Although factory zuma exhausts (except the very worst ones) should have some form of taper, the sports expansion chambers for 2-strokes are designed better.

Ruckus exhaust accessories Ruckus parts Yamaha scooter parts Zuma 125, Dr Pulley, Stage6, Polini, Yoshimura, NGK, Malossi, NCY & OEM replacement parts at DrowSports. For more details please visit http://www.drowsports.com/