1965 Yamaha YM1 305cc Motorcycle

Description

A relative latecomer to the motorcycle market, Yamaha’s first model – the YA-1 – was launched in 1955 and the company quickly established itself through competition success, both at home and abroad.  A series of models based on contemporary German DKW and Adler designs followed, including the two-stroke YD-1.  It’s successor, the YDS-2, redefined the 250cc market, putting racing technology into a mass produced road bike.  Powered by a two-stroke parallel twin with a bore and stroke of 56mm x 50mm, the YDS-2 had a single piston-port intake and exhaust per cylinder, with twin transfer ports.  The five-speed gearbox used a crank-mounted clutch, which ultimately became the Yamaha’s achilles heel – the design was revised several times and the clutch shaft diameter was increased to 25mm on the YDS-3 in an effort to avoid disaster.  The list of standard features was impressive - a duplex frame, three-way adjustable rear shock absorbers, twin leading shoe front brake and adjustable friction steering damper, plus steering lock and tyre pump as standard.  Three paint colours were offered; most were either red or blue with a white pearl finish on the fuel tank but a small number came in black with fern silver tank and side panels.  Yamaha entered the larger 350cc class in 1965 with a development of the YDS-3 – designated the YM-1, the new model was bored and stroked out to 305cc, upping the power output to 26 horsepower.  The flagship model of Yamaha’s sport bike range, the YM-1 also boasted the clever ‘Autolube’ separate oil supply system and twin carburettors.  Capable of reaching speeds of around 100mph, an impressive figure for such a small capacity bike, the Yamaha is now very popular with collectors but few exist in Australia, making this a real rarity.