Positioned in Yamaha's sport touring motorcycle lineup, the 1968 Yamaha AS1 utilizes a 125 cc (7.6 cu in) air-cooled twin, two-stroke layout. In factory specification, peak output is rated at 15 HP (10.9 kW) at 8,500 rpm while maximum torque reaches 12.7 Nm (9.4 lb-ft) at 8,000 rpm, transferring power to the rear wheel through a 5-speed gearbox and chain final drive. With a specific output of 120 HP per liter and a 500 rpm working window between peak torque (8,000 rpm) and peak power (8,500 rpm), the engine character is reflecting a performance-oriented street tune that balances strong mid-range pull with an energetic top-end rush.
On the scales, the AS1 measures 98 kg (216 lbs) dry, translating to a power-to-weight ratio of 0.15 HP/kg (6.53 kg per horsepower). Rider ergonomics and chassis geometry center around a 1,072 mm (42.2 in) wheelbase engineered for quick, flickable steering geometry. The 9.46-liter (2.5 US gal) fuel tank supports practical everyday commuting and weekend road stints, while factory top speed is listed at 121 km/h (75 mph).
Specific Output
120 HP/L
Power-to-Weight
0.15 HP/kg (6.53 kg/HP)
Power Band Window
8,000–8,500 rpm
Engine
Displacement125.0 ccm (7.63 cubic inches)
Engine TypeTwin, two-stroke
Engine DetailsTwin, two-stroke
Power15.0 HP (10.9 kW)) @ 8500 RPM
Torque12.7 Nm (1.3 kgf-m or 9.4 ft.lbs) @ 8000 RPM
Compression7.0:1
Bore x Stroke43.0 x 43.0 mm (1.7 x 1.7 inches)
Fuel SystemCarburettor
Fuel ControlPort control
IgnitionPoints
LubricationAutolube
CoolingAir
Max RPM8500
Transmission
Gearbox5-speed
Final DriveChain (final drive)
Performance
Top Speed120.7 km/h (75.0 mph)
ExhaustTwin chrome
Chassis
Frame TypeSteel tube
Front SuspensionTelescopic
Rear SuspensionSwinging arm, coil spring oil damper
Wheelbase1072 mm (42.2 inches)
Ground Clearance150 mm (5.9 inches)
Wheels & Brakes
Front Tyre-2.50-18
Front BrakesExpanding brake (drum brake). single leading shoe
Use this page to compare this motorcycle by its real specifications, not only by model name. Focus on the details that affect fit, comfort, handling, range and ownership.
Power
Compare engine output with similar motorcycles if acceleration, highway use or two-up riding matters.
Torque
Torque is useful for judging real-world pull, especially for touring, commuting and loaded riding.
Weight
Compare weight carefully because it affects low-speed handling, parking and confidence.
Fuel Capacity
Fuel capacity helps estimate touring range and how often you may need to stop.
Brakes
Brake setup is worth comparing if you ride in traffic, mountains or with a passenger.
Suspension
Suspension details can matter for comfort, road feel and long-distance riding.
Transmission
Transmission and final drive affect maintenance, smoothness and everyday usability.
