The Yamaha DT125 is a
motorcycle
A motorcycle (motorbike, bike, or trike (if three-wheeled)) is a two or three-wheeled motor vehicle steered by a handlebar. Motorcycle design varies greatly to suit a range of different purposes: long-distance travel, commuting, cruising ...
produced by
Yamaha Motor Company
is a Japanese multinational manufacturer of motorcycles, marine products such as boats and outboard motors, and other motorized products. The company was established in 1955 upon separation from Yamaha Corporation (however, Yamaha Corporation ...
that was first launched in 1974 as the DT125A
[ and is still sold in some markets to this day. The model designation DT indicates that it is a ]two-stroke
A two-stroke (or two-stroke cycle) engine is a type of internal combustion engine that completes a Thermodynamic power cycle, power cycle with two strokes (up and down movements) of the piston during one power cycle, this power cycle being comple ...
, off-road-styled motorcycle, it has a raised exhaust, handlebars with cross members, universal tires, and adequate ground clearance for an off-road enduro
Enduro is a form of motorcycle sport run on extended cross-country, off-road courses. Enduro consists of many different obstacles and challenges. The main type of enduro event, and the format to which the World Enduro Championship is run, is a ...
motorcycle or trail motorcycle. The USA received the last DT125H in 1981.
When first launched, the DT125 had a single-cylinder, air-cooled, two-stroke engine, a cradle-style tubular steel frame, conventional telescopic front forks and dual shock swingarm rear suspension, and drum brakes front and rear. Over the years the model received numerous updates and restyles, the dates and specifications of which vary between markets. Notable changes include the appearance of a single shock absorber rear swingarm in 1977, which Yamaha referred to as Mono-cross, or MX for short, a feature that appeared on many of Yamaha's other small and medium-sized motorcycles at a similar time.
In 1982 the DT125 received a major restyle and gained a liquid-cooled engine to become the DT125LC. In 1984 the electrics were upgraded to 12v and YPVS {{Unreferenced, date=February 2018
The two-stroke power valve system is an improvement to a conventional two-stroke engine that gives a high power output over a wider RPM range.
Operation of a two-stroke engine
A '' stroke'' is the action of a p ...
was added, the front brake drum was changed to a disc, and rising rate rear suspension was fitted with the introduction of the DT125LC mk3. Another restyle in 1987 brought the DT125R, the most noticeable specification change being the swap to a rear disc brake.
References
DT125
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