Yamaha IT 490

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Yamaha IT490

The IT 490 is an enduro that was designed for use in competitions.

It was built mainly for the American, but also for the French market. Only small numbers of items were imported into Germany, and only through gray imports . It differs from other enduros with its unusually large two-stroke engine . It is the largest 2-stroke enduro that Yamaha Motor has ever produced. The model was discontinued after two years of construction, in 1983 and 1984.

precursor

The motorcycle is a further development of the IT 400 , which has been built since 1976. There is a clear relationship to the motocross models of the YZ series, which are still built today. Often, technical developments of the YZ series were later adopted in the IT series.

The IT series differs from the much more well-known DT Enduro models in that it is designed to be uncompromising for competitive use, while the DT is perfectly suitable for everyday use.

The predecessors of the IT 490 include the better-known DT 400 , but also the SC 500 , which is quite unknown in Germany .

successor

The IT 490 represents the last step in the development of large-volume IT enduros. After it was discontinued in 1984, there was only a successor in 1992 with the WR 500 . In these eight years, however, there was hardly any real development. B. the motor practically identical to the motor of the IT 490 .

It was not until six years later that Yamaha brought a pioneering successor to the market with the WR 400 . This new WR brought the breakthrough for 4-stroke engines (Otto engine) in enduro sport and thus contributed significantly to the displacement of the two-stroke engine from motorcycle off-road racing.

Special

The IT 490 belongs to the small group of half-liter two-stroke enduros. This type of motorcycle is very rare nowadays because the development of the two-stroke engine has practically stopped in the last few decades. Their position has been replaced by more easily drivable and more environmentally friendly 4-stroke engines. The 500 cm 3 class for two-stroke enduros is relatively unpopular compared to the 250 cm 3 and 125 cm 3 classes, as the motorcycles develop such a high level of performance that only a few drivers can control them in competition. 250 cm 3 enduro bikes are also faster on many routes, as they compensate for their performance deficit with better handling, smoother power output and lower weight.

IT is the first enduro from Yamaha to use monocross rear suspension. As a result, much larger spring travel could be achieved than with the previously used stereo suspension struts or a cantilever system. The spring travel is 300 mm at the front and rear, which is still the current standard.

YEIS was used on this machine .

Technical specifications

Dimensions

  • Length: 2190 mm
  • Width: 850 mm
  • Height: 1300 mm
  • Seat height: 945 mm
  • Wheelbase: 1485 mm
  • Ground clearance: 340 mm
  • Weight: 124 kg (including oil and petrol)

engine

  • Type: 2 stroke, air-cooled
  • Cylinder: 1 cylinder standing
  • Displacement: 487 cm³
  • Bore × stroke: 87 × 82 mm
  • Compression: 6.9: 1
  • Starting system: Kickstarter

landing gear

  • Frame type: closed two-loop frame
  • Steering head angle: 28 °
  • Trail: 118 mm
  • Tire size V: 3.00 - 21 - 4PR
  • Tire size H: 150/80 - 18 - 4PR
  • Front brake: Duplex drum brake
  • Rear brake: Simplex drum brake
  • Front suspension: air-assisted telescopic fork, 300 mm travel
  • Rear suspension: light metal swing arm (monocross), 300 mm spring travel, adjustable damping

See also

Web links