One of the world's first mass-produced sport bikes, the Yamaha DT 125 was an enduro motorcycle produced by the Yamaha Motor Company between 1968 and 2008. A powerful but lightweight bike, the DT 125 was designed to be agile and quick when racing over treacherous off-road and obstacle-heavy enduro courses.
The Yamaha DT 125 had a liquid-cooled, single-cylinder, two-stroke engine with a membrane fuel intake system and a capacity of 124cc. It had a 56-mm bore with a 50.7-mm stroke. Its compression ratio was 6.8:1. Its nominal power output was 14.75 horsepower at 7,000rpm, and its maximum torque was 11.6 foot-pounds at 6,500rpm. It had a Mikuni TM 28 SS carburettor and a six-gear manual transmission. Its gear ratios ranged from 2.833:1 to 0.818:1. It had a multi-disc clutch in an oil bath and a high-voltage capacitor ignition. It had a 12-volt battery and an alternating-current generator.
Suspension, Brakes and Wheels
The DT 125's front suspension consisted of a 270-mm telescopic fork, and its rear suspension was of the monocross type and measured 260mm. Both front and rear brakes were disc-type. The front measured 230mm and the rear measured 220mm. The front tire measured 2.75 inches in width and 21 inches in diameter, and the rear tire measured 4.1 inches in width and 18 inches in diameter. The wheelbase measured 55.1 inches.
Overall, the bike measured 88.6 inches long by 32.7 inches wide by 49.4 inches tall. Its curb weight was approximately 109kg., and its maximum weight was 3020kg. Its seat was 35.4 inches high and 29.1 inches long. Its fuel tank held 2.64 gallons, with 0.47 gallons in reserve. Its top speed was 71.5mph. Its frame was made of double steel pipes. Its steering angle was 27.5 degrees, and its caster measured 113mm.