Lot details
Registration No: N/A
Frame No: 2K8-006567
Engine No: 2K8-002791
cc: 400
MOT Expiry Date: N/A

Yamaha's introduction of their monocross rear suspension system marked a significant step forwards in chassis design for off road motorcycles and marked an escalation in the "suspension war" between manufacturers. This had seen a gradual increase in suspension travel as different manufacturers sought an edge over their rivals. The system had first been seen on the works machines during 1973 before being introduced to the public for the 1974 season on the YZ250. In its initial form the swinging arm was of tubular steel construction. The shock absorber was mounted under the fuel tank and connected to the swinging arm via a tubular steel vee piece.
For the 1978 YZ400 Yamaha changed the material that the swinging arm was manufactured from tubular steel to box section aluminium alloy and increased both the front and rear suspension travel.
This example has been restored to a good standard cosmetically and is attractively presented in the distinctive yellow and black livery of the North American market models. It has formed part of private collection from which it is now offered.