Yamaha GT80: history, specs, pictures

From CycleChaos
Jump to navigation Jump to search
Yamaha GT80
Also called GT80/MX
Production 1973 - 1980
Class Enduro
single cylinder, two-stroke
Bore / Stroke 47.0mm x 42.0mm
Top Speed 57 mph (91 km/h)
Torque 4.5 ft/lbs (6.1 Nm) @ 7200RPM
Fuel System carburetor. teikei
Ignition points type ignition
Spark Plug NGK B7HS '73-80 [1]
Battery YUASA 6N4-2A-5 '73-80 [1]
Transmission Gear box: 4-speed
Clutch: wet plate
Final Drive Chain: 420x
Suspension Front: inverted forks
Rear: non-adjustable dual shock
Brakes Front: expanding brake (drum brake)
Rear: expanding brake (drum brake)
Front Tire 2.50-15 '73-80 [1]
Rear Tire 2.75-14 '73-80 [1]
Weight 130.07 pounds (59.0 Kg) (dry), 60.3 kg (wet)
Recommended Oil Yamalube 10w-40
Fuel Capacity 1.3 Gallon (4.92 Liters)
Manuals Service Manual

The Yamaha GT80 B was a single cylinder, two-stroke standard produced by Yamaha in 1975. It could reach a top speed of 57 mph (91 km/h). Max torque was 4.5 ft/lbs (6.1 Nm) @ 7200 RPM.


The engine was a air cooled single cylinder, two-stroke. A 47.0mm bore x 42.0mm stroke result in a displacement of just 72.0 cubic centimeters.


The bike has a 4-speed transmission. Power was moderated via the wet plate.


It came with a 2.50-15 front tire and a 2.75-14 rear tire. Stopping was achieved via expanding brake (drum brake) in the front and a expanding brake (drum brake) in the rear. The front suspension was a inverted forks while the rear was equipped with a non-adjustable dual shock. The GT80 B was fitted with a 1.3 Gallon (4.92 Liters) fuel tank. The bike weighed just 130.07 pounds (59.0 Kg).




1980 Yamaha GT80 in Red
1980 Yamaha GT80 in Red
1980 Yamaha GT80 in Red


1981 Yamaha GT80 in Blue
1981 Yamaha GT80 in Blue
1981 Yamaha GT80 in Blue
1981 Yamaha GT80 in Blue


  1. 1.0 1.1 1.2 1.3 2019 Western Power Sports Catalog. Western Power Sports. 2019.