Yamaha IT490

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Yamaha IT490
Also called IT 490
Production 1983 - 1984
Class Enduro
Predecessor Yamaha IT465
Two stroke, single cylinder, read valve, air cooled
Bore / Stroke 86.4mm x 86.4mm
Compression ratio 4.9:1
Top Speed 80 mph
Horsepower 35.0 HP (26.1 KW) @ 6000RPM
Torque 30.98 ft/lbs (42.0 Nm) @ 5500RPM
Ignition cdi
Spark Plug NGK B8ES '83-84
Transmission Gear box: 5-Speed

Final Drive: Chain

Clutch: Wet multi-discs
Final Drive Chain: 520x110 ‘83-84[1]
Front Sprocket 14T ‘83-84[1]
Rear Sprocket 44T ‘83-84[1]
Suspension Front: 43mm Telescopic adjustable forks
Rear: Mono shock, adjustable spring preload and rebound damping
Brakes Front: Drum
Rear: Drum
Front Tire 3.00 -21
Rear Tire 150/80 -18
Wheelbase 56.5 inches (1435 mm)
Seat Height 37.2 inches (945 mm)
Weight 275.58 pounds (125.0 Kg) (dry), 123.0 kg (wet)
Recommended Oil Yamalube 10w-40
Fuel Capacity 3.59 Gallon (13.60 Liters)
Related Yamaha IT125, Yamaha IT175, Yamaha IT200, Yamaha IT250, Yamaha IT350, Yamaha IT490, Yamaha IT500, Yamaha YZ490
Competition Honda CR500, Kawasaki KX500
Manuals Service Manual

The Yamaha IT 490 was a Two stroke, single cylinder, read valve, air cooled Enduro motorcycle produced by Yamaha between 1983 and 1984. Max torque was 30.98 ft/lbs (42.0 Nm) @ 5500 RPM. Claimed horsepower was 35.0 HP (26.1 KW) @ 6000 RPM.


The engine was a air cooled Two stroke, single cylinder, read valve, air cooled. A 86.4mm bore x 86.4mm stroke result in a displacement of just 490.0 cubic centimeters.


The bike has a 5-Speed transmission. Power was moderated via the Wet multi-discs.


It came with a 3.00 -21 front tire and a 150/80 -18 rear tire. Stopping was achieved via Drum in the front and a Drum in the rear. The front suspension was a 43mm Telescopic adjustable forks while the rear was equipped with a Mono shock, adjustable spring preload and rebound damping. The IT 490 was fitted with a 3.59 Gallon (13.60 Liters) fuel tank. The bike weighed just 275.58 pounds (125.0 Kg). The wheelbase was 56.5 inches (1435 mm) long.


1984 Yamaha IT 490[edit]

The big news in the powerplant is the bump in displacement from 465 to 487cc, accomplished simply by increasing the cylinder bore two millimeters. This follows the large, seven-millimeter increase in stroke which boosted the IT's displacement from 425 to 465cc in 1981. Aside from the trendiness involved in increasing their open-classers' engine sizes, most manufacturers are nudging 500cc because more displacement is the most straightforward route to better power.

See Also[edit]


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