Steel Spoke Specification Example for Off-Road Bikes: Sealed Unit
Steel Spoke Specification Example for Off-Road Bikes: Sealed Unit
This is a worked specification for steel spoke in a sealed unit programme. It is the document we would send a buyer who asks what exactly they are getting: the material, the dimensions that are actually controlled, the finish, and the checks that happen before anything is packed.
The sealed unit version exists because the duty cycle on off-road bikes is not the same as on a showroom vehicle. Where the two are specified identically, something fails later — usually lead time that slipped twice before bulk started.

Example specification
| Item | Steel Spoke |
|---|---|
| Application | Off-Road Bikes |
| Version | Sealed Unit |
| Base material | Magnesium Alloy |
| Controlled dimensions | 6 key dimensions, recorded per lot |
| Tolerance band | ±0.05 mm |
| Finish | zinc plated |
| MOQ | 3,000 pieces per specification |
| Sampling | 14 working days, 3 days per revision |
| Compliance | ISO 9001 |
How the example is built up
- Start from the duty cycle, not from the catalogue photograph.
- Fix the base material in writing — Magnesium Alloy, in this example.
- List the dimensions that are actually controlled and the tolerance on each.
- Name the finish and what it has to survive.
- State the inspection level and who pays when a lot fails.

Processes involved
- surface grinding
- CNC machining
- precision stamping
- electroplating
- injection moulding
- anodising
Where this example applies
Programmes that run sealed unit most often specify this build for off-road bikes. Related applications include courier fleets, boat trailers, scooter fleets, racing teams, delivery vans.
Checks before packing
- Dimensional report against the approved drawing.
- AQL 2.5 sampling on the finished lot.
- Finish inspection under agreed lighting.
- Carton drop test on the first lot of a new packing specification.
Questions buyers ask
What happens if a lot fails inspection?
The lot is re-inspected against the golden sample, and replacement pieces ship on the next available booking at our cost.
What testing is included?
Standard lots ship with dimensional and hardness reports. ISO 9001 documentation is issued with the shipment when your market requires it.
What is the minimum order quantity?
The standard MOQ is 3000 pieces per specification. Mixed sizes inside one shipment are accepted once the total reaches that figure.
How is packing specified?
Individual packing, inner box quantity and carton marking are confirmed at quotation stage so the cartons arrive ready for your warehouse.
Ask for the current catalogue and the specification sheet for this line.



