It appears you're interested in specifications for the Yamaha YZ450F. This Cross / motocross model is powered by a Single cylinder, four-stroke engine with 449.00 ccm (27.40 cubic inches) of actual displacement before 12.3:1 compression. Fueling is metered via Carburettor. Keihin FCR MX39 allowing this machine to produce its horsepower and torque. According to our records engine heat of the Yamaha YZ450F is moderated by Liquid. You'll need to get familiar with the 5-speed transmission and pay attention to final drive Chain maintainence. Our best information shows that the front tire size is 80/80-21 and the rear is 120/80-19 . 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 Single disc rear brakes. The Yamaha YZ450F was launched in 2009, 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.