The Yamaha TDM is an 849 cc DOHC parallel-twin motorcycle that heralded the modern "Sport touring" category. The TDM was first manufactured by the Yamaha Motor Company of Japan in 1991. The TDM has a pressed-steel frame and a dry sump engine with five valves per cylinder, (three inlet and two exhaust).

The TDM was arguably the first road-oriented "Adventure Sports" motorcycle. It was not intended as an off-road machine, but as a comfortable yet manoeuvrable all-rounder, rather like the Ducati Multistrada of later years. A TDM is too bulky and heavy for serious off-road work, but its long-travel suspension can cope with gravel tracks.

The TDM's engine was derived from the Paris Dakar winning Yamaha XTZ 750 Super Tenere. Yamaha intended to create a motorcycle capable of handling European mountain roads and coping with rougher road surfaces. The TDM's upright riding position seemed radical in its day.^{[citation needed]}

The TDM was imported into the United States for only two years, 1992 and 1993. It was never a big seller in the United Kingdom nor at first in The Netherlands, but sales were strong in other European countries, particularly in France, Germany and Greece.^{[citation needed]}.

In 1996, instead of the previous 360 engine Yamaha released the Mk II TDM with updated bodywork and a 270° firing order engine that was shared with the TRX850, they also shared the same transmission.^[2][3] This new engine was first seen in 1995, when Yamaha introduced its TRX850 in Japan.

Although early models came with no fuel gauge and a reserve fuel tap, beginning in 1999, Yamaha replaced the temperature gauge on the dashboard with a fuel gauge.

In 2001 the TDM850 was succeeded by the TDM 900, a more powerful bike with a similar concept to the 850. The TDM900 featured new bodywork, a diamond-shaped alloy frame, a 6-speed gearbox, fuel-injection, R1-derived brakes, a reduced dry weight of 190 kg, a larger-capacity 900cc engine, and slightly wider tyres (160 rear, 120 front). It has a 2-position trip meter, a digital clock, and digital fuel meter. ABS was available as an option. The engine has a maximum power output of 84.8 hp (63.2 kW) @ 7,500 rpm and torque 65.49 lb⋅ft (88.79 N⋅m) @ 7,500 rpm (claimed).^[4]

MCN said of the TDM850 Mk II: "Fairly revolutionary when launched and certainly years ahead of its time, the Yamaha TDM850 was a sort of Multistrada 12 years before Ducati thought of it. As a serious ‘street trailie allrounder' it’s pretty effective too. The later 900 is better, but the Yamaha TDM850 is still decent, good value, different, and largely overlooked".^[1]