It appears you're interested in specifications for the Yamaha Why. This Scooter model is powered by a Single cylinder, two-stroke engine with 49.00 ccm (2.99 cubic inches) of actual displacement before 7.3:1 compression. Fueling is metered via Carburettor. Gurtner PY-12 allowing this machine to produce its 3.21 HP (2.3 kW) horsepower and 3.50 Nm (0.4 kgf-m or 2.6 ft.lbs) torque. According to our records engine heat of the Yamaha Why is moderated by Air. You'll need to get familiar with the Automatic transmission and pay attention to final drive Belt maintainence. Our best information shows that the front tire size is 70/90-16 and the rear is 80/90-16 . The entire package is supported by the frame, . We know you like to go fast or cruise all day, but when you need to stop, you'll be dependant on Single disc front brakes and Expanding brake (drum brake) rear brakes. The Yamaha Why was launched in 2007, and we're happy to know (or assume) you've got one in your garage. To help you keep your ride in tip-top shape, consider purchasing an owner or service manual.