It appears you're interested in specifications for the BSA Y13. This Cross / motocross model is powered by a Twin, four-stroke engine with 748.00 ccm (45.64 cubic inches) of actual displacement before compression. Fueling is metered via Carburettor. Amal monoblock allowing this machine to produce its 19.50 HP (14.2 kW) horsepower and torque. According to our records engine heat of the BSA Y13 is moderated by Air. You'll need to get familiar with the transmission and pay attention to final drive Chain maintainence. Our best information shows that the front tire size is 4.00-18 and the rear is 4.00-18 . The entire package is supported by the frame, Duplex cradle. 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 BSA Y13 was launched in 1938, 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.