It appears you're interested in specifications for the NSU 501 OSL. This Sport model is powered by a Single cylinder, four-stroke engine with 494.00 ccm (30.14 cubic inches) of actual displacement before compression. Fueling is metered via Carburettor. Graetzin KE 27/45 allowing this machine to produce its 22.00 HP (16.1 kW) horsepower and torque. According to our records engine heat of the NSU 501 OSL is moderated by Air. You'll need to get familiar with the transmission and pay attention to final drive maintainence. Our best information shows that the front tire size is 3.25-19 and the rear is 3.25-19 . The entire package is supported by the frame, Steel. 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 NSU 501 OSL was launched in 1937, 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.