ISO 6054-2:1990

Overview

ISO 6054-2:1990 specifies rim dimensions for inch-code-designated motorcycle tyres covering diameter codes 4 to 12. As Part 2 of the ISO 6054 series, this standard defines the rim contours and diameters needed for safe mounting and fitment of tyres (the tyre designations, dimensions and load ratings are given in ISO 6054‑1). This second edition (1990) cancels and replaces the 1986 edition and includes updated figures, clauses and tables relevant to modern rim types.

Keywords: ISO 6054-2, motorcycle rims, rim dimensions, diameter codes, inch-code-designated, rim designation

Key topics and technical requirements

• Scope and designation
  • Applies to inch-code-designated motorcycle rims for diameter codes 4–12.
  • Rims are designated per ISO 3911 (example format: “8 x 2.10” = nominal diameter code and nominal rim width code).
• Rim types covered
  • Divided rims - contour dimensions and tolerances (table and figure references).
  • Drop-centre rims - contour and diameter specifications for mounting tyres.
  • Tapered bead seat rims (MT type) - contour and bead-seat dimensions, with specific provisions for rims without a hump.
• Recommended rim widths
  • Recommended rim widths vs nominal tyre section widths are provided (table of recommended pairings).
• Rim circumference measurement (Annex A - normative)
  • Procedure using a mandrel diameter and tape gauge; mandrel diameters and tape circumferences are tabulated.
  • Mandrel diameter tolerance indicated (±0.5 mm).
• Finish and safety details
  • Requirements for smooth rim contours, rounded/chamfered valve-hole edges, and burr-free hub-side edges to avoid valve or tyre damage.

Applications and users

ISO 6054-2 is used by:

• Motorcycle wheel and rim designers and manufacturers (for dimensioning and production).
• Tyre manufacturers (ensuring tyre-to-rim compatibility for inch code tyres).
• OEMs and aftermarket wheel suppliers (component selection and quality control).
• Testing laboratories and inspection agencies (dimensional verification, rim circumference measurement).
• Vehicle safety regulators and repair/maintenance workshops (fitment guidance and compliance).

Practical benefits: ensures interchangeability between tyres and rims, improves safety during tyre mounting, and standardizes manufacturing tolerances across the supply chain.

Related standards

• ISO 6054-1 - Motorcycle tyres (code-designated series) - Tyres
• ISO 3911 - Wheel rims nomenclature, designation and marking
• Other complementary documents noted in ISO 6054 series (e.g., standards addressing larger tyre sizes and metric-series equivalents)

For engineers and procurement teams working with motorcycle wheels, ISO 6054-2:1990 provides the authoritative rim dimension and measurement rules necessary to ensure correct tyre fitment and manufacturing consistency.