The Perfect Balance: Yamaha TY175
Superb lightweight engineering and years of invaluable experience in off-road competition have enabled Yamaha to produce, in the TY175, one of the most effective trials machines on the market. A ·slim, light, high-tensile steel frame with a specially developed engine perfectly poised for balance and manoeuvrability forms the basis of a devastatingly effective competition machine. Refinements include a flywheel magneto ignition system designed to produce a strong spark at low engine speeds and a chain tensioner to enhance rider control. The TYl75 has quickly become recognised as one of the finest lightweight trials machines in the world.
A six-speed gearbox with carefully selected, widely spaced ratios enables the TY’s power to be most effectively used through the sections or between them.
A single-cylinder 171cm3 engine has been specially developed to produce low-speed torque while retaining useful power throughout the rev range. Aultolube lubrication, supplying oil under pressure from a separate tank, not only ensures reliability but leads to a clean, swift throttle response. Urgent low-speed punch is guaranteed by Yamaha’s Torque Induction reed-valve system, which utilises fluctuations in crankcase pressure to deliver precisely the measure of fuel required.
Yamaha’s experience in world-class trials, particularly in drawing upon the development riding expertise of Mick Andrews, has led to the creation of the TY’s light, high-tensile steel frame. The engine is located for optimum balance and maximum manoeuvrability and the machine J as a whole has an exceptional power-to-weight ratio.
Street-legal speedometer is well protected behind left fork leg; ignition system, fired by a crankshaft mounted magnet, is specially designed to produce a fat spark at low engine speeds; chain tensioner absorbs slack and improves control; aluminium bash plate protects engine; special silencing system enhances enjoyment of the country side.
Heavy duty long-travel front forks with slow, positive damping are used in conjunction with rear units capable of five-way adjustment.
Yamaha’s special labyrinth seal, double- ridge brake plates on both front and rear drums prevent water and dust from penetrating.
Type 2-stroke, 1-cylinder
Displacement 171 cm3
Bore & Stroke 66 x 50 mm
Compression ratio 5 .8: 1
Max. horsepower 8.8 kW (12 PS) @7,000 rev./min.
Max. torque 13.7 Nm (1.4 kg—m) @6,000 rev./min.
Lubrication system Autolube
Starting system Kick starter
Primary transmission Gear
Final transmission Chain
Clutch Multi-plate, wet
Charging system Flywheel magneto
Ignition system Magneto
Overall length 1,955 mm
Overall width 835 mm
Overall height 1,100 mm
Wheelbase 1,265 mm
Seat height 750 mm
Ground clearance. .r 295 mm
Weight (net) 81.0 kg.
Fuel tank capacity 4.0 lit.
Oil tank capacity 0.3 lit.
Front 2.75-21 -4PR