About the Yamaha MX400
Fork, steering and control parts for an MX400 restoration.
Yamaha’s period MX400B brochure describes a two-stroke single built for the dirt. A restoration may retain its original chassis or include forks and controls fitted later, so identify the equipment on the motorcycle before choosing service parts. This selection concentrates on fork seals, steering bearings and handlebar controls.
Refresh the front end and controls
For a fork leak, compare seal dimensions and inspect the sliding surfaces. For steering play or roughness, inspect the bearings, races and seating surfaces before deciding what the repair needs. A replacement lever must match the perch, pivot and cable end. The featured products list MX400 1975; each still needs the relevant assembly check.
Know your model before choosing partsYamaha MX400 repair checkpoints
Use the complete model, year and fitted assembly. Each product has its own application and package contents.
Fork seals
The featured set lists MX400 1975 with a 34 × 46 × 10.5 specification. Compare all dimensions, not just the fork-tube diameter.
Steering bearings
The linked steering kit lists MX400 1975. Inspect bearing seats and compare the included races and seals before assembly.
Clutch controls
The clutch lever lists MX400 1975. Match the pivot, perch and cable-end arrangement on the fitted handlebar.
Identify your model before orderingYamaha MX400 identification checklist
Use the identification on your machine and the component being repaired.
- Read the full MX400 model and model year.
- Record fork-seal markings and inspect the tubes before choosing new seals.
- Photograph the steering bearings or lever pivot when replacement chassis parts are fitted.
Contact PartsNMore with the complete model, year and clear photos of the identification and original part.