Overview
ISO 11486:2006 - "Motorcycles - Methods for setting running resistance on a chassis dynamometer" defines standardized methods to determine and reproduce a motorcycle’s running resistance on a chassis dynamometer. The standard describes a measured on‑road method (the coastdown method) and a simpler running resistance table (table method) for setting dynamometer load and inertia. It is intended for motorcycles as defined in ISO 3833 and supports reliable fuel consumption and exhaust emission testing by ensuring consistent dynamometer settings.
Key topics and technical requirements
- Scope and methods
- Two primary setting methods: coastdown method (individual on‑road measurement) and table method (inertia-based approximation).
- Applicable for exhaust emission and fuel consumption testing where dynamometer running resistance must match on‑road behaviour.
- Road test requirements
- Road: flat, level, straight, smoothly paved; slope ≤ 0.5 %.
- Ambient limits: wind steady; max wind speed 3 m/s (gusts 5 m/s); temperature range 278 K to 308 K; relative humidity ≤ 95 %.
- Standard ambient reference: pressure 100 kPa, temperature 293 K, reference air density 1.189 kg/m³.
- Speeds and measurements
- Defines specified speeds (at least four points including the reference speed) and reference speed(s) used to calculate target resistance.
- Coastdown start speed must be sufficiently above the measurement start to allow procedures (see standard).
- Accuracy and instrumentation
- Measurement accuracy requirements include: running resistance force ±2 %; motorcycle speed ±1 % (resolution 0.45 km/h); coastdown time ±0.5 % (0.01 s); total motorcycle mass ±1.0 %.
- Annexes specify required documentation: motorcycle description (Annex A) and dynamometer/instrument description (Annex B).
- Data processing
- Procedures for calculating running resistance, curve fitting, deriving target running resistance forces, inertia settings, warming‑up, tyre pressure and verification checks.
Applications and users
ISO 11486:2006 is used by:
- Motorcycle manufacturers for certification and R&D.
- Independent test laboratories performing fuel consumption and exhaust emissions measurements.
- Regulatory agencies and homologation bodies requiring reproducible dynamometer settings.
- Chassis dynamometer manufacturers and calibration engineers implementing target resistance and inertia settings.
Practical benefits: consistent on‑road to laboratory correlation, reproducible test results, and compliance with international test procedures.
Related standards
- ISO 3833 - Road vehicles: types, terms and definitions (applicability to motorcycle definitions).
- ISO 7117 - Motorcycles: measurement of maximum speed.
For implementation, follow the instrument and test method requirements referenced in ISO 11486:2006 and the applicable emission or fuel consumption test standards.
