It appears you're interested in specifications for the Jawa 90 Roadster. This Classic model is powered by a Single cylinder, two-stroke engine with 88.70 ccm (5.41 cubic inches) of actual displacement before 8.5:1 compression. Fueling is metered via Carburettor. Jikov allowing this machine to produce its 10.20 HP (7.4 kW) horsepower and 6.35 Nm (0.6 kgf-m or 4.7 ft.lbs) torque. According to our records engine heat of the Jawa 90 Roadster is moderated by Air. 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 2.5-18 and the rear is 2.75-18 . 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 Expanding brake (drum brake) front brakes and Expanding brake (drum brake) rear brakes. The Jawa 90 Roadster was launched in 1969, 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.