|
Make Model |
Yamaha IT 425 |
|
Year |
1980 |
|
Engine |
Air cooled, two stroke, single cylinder |
|
Capacity |
425 |
| Bore x Stroke | |
| Compression Ratio | 4.9;1 |
|
Induction |
38mm Mikuni |
|
Ignition / Starting |
CDI / kick |
|
Max Power |
35 hp @ 6000 rpm (rear tyre |
|
Max Torque |
31 lb-ft @ 5500 rpm |
|
Transmission / Drive |
5 Speed / chain |
|
Front Suspension |
43mm Telescopic adjustable forks, 300mm wheel travel |
|
Rear Suspension |
Mono shock, adjustable spring preload and rebound damping, 300mm wheel travel |
|
Front Brakes |
Drum |
|
Rear Brakes |
Drum |
|
Front Tyre |
3.00 -21 |
|
Rear Tyre |
150/80 -18 |
|
Dry-Weight |
125 kg |
|
Fuel Capacity |
13.6 Litres |
The IT425 which for the first time brought 'professional'-type performance within the grasp of anybody able or willing to expend approximately £1,200 in pursuit of his chosen pastime of enduro racing (or fastgreen-laning).
Based on the YZ400 moto-crosser, with a triangulated rear frame and a single monoshock damper with variable loading, the IT (for International Trial) 425 had an air-assisted leading-axle front fork and very complete equipment, running even to a small headlamp powered from a flywheel generator.
The engine, however, tucked away in a lightweight, 56in-wheelbase chassis, justifiably took most attention on account of both its all-black good looks and its specification which, while keeping to nothing more outlandish than a five-port layout, with reed valve for induction, managed to churn out 46 bhp at 6,500 rpm, providing plenty of outright speed
