About the Honda ST90
Mighty Dax identity, fork dimensions and separate front and rear brake applications.
The Honda ST90 Mighty Dax uses a horizontal four-stroke OHC engine. This guide focuses on its 1973–1975 fork seals, front and rear brake shoes, and individual clutch plates.
Build a brake and fork service order
Choose shoes for the brake position being repaired and compare the fitted fork with the 27 × 39 × 10.5 mm oil-seal pair. If the engine has been replaced, identify it before selecting clutch parts.
Know your ST90 before choosing partsST90 repair checkpoints
Start with the complete model and year, then check the assembly being repaired.
Front fork
27 × 39 × 10.5 mm seals
The featured fork oil seals list ST90 1973–1975 and are supplied as a set of two.
Brake shoes
Choose the correct position
Separate front and rear shoe listings include ST90 1973–1975.
Clutch
Individual plate replacement
The linked clutch plate lists ST90 1973–1975 and is sold individually.
Identify your motorcycle before orderingST90 identification checklist
Use these checks when a registration year or a model badge does not identify the fitted parts.
- ST90 designation and model year checked against the motorcycle and documents.
- Frame and engine markings, including known replacement-engine details.
- Fork assembly and full removed-seal dimensions.
- Front or rear brake position and the fitted wheel and brake assembly.
Contact PartsNMore with the model year, frame and engine markings, and clear photographs of the component being repaired.