Overview
ISO 17479:2013 - "Motorcycles - Measurement methods for gaseous exhaust emissions during inspection or maintenance" specifies direct measurement methods for gaseous exhaust emissions from motorcycles (spark-ignition, two‑stroke or four‑stroke) under the no‑load (idling) engine operating condition. The standard is intended for use during periodic inspections, official roadside checks, and maintenance or diagnostic operations to assess concentrations of CO, HC and CO2 at idling.
Key topics and requirements
- Scope and applicability: Applies to motorcycles as defined in ISO 3833 with spark‑ignition engines; measurement at idling condition.
- Instrumentation: Requires an exhaust gas analyser meeting ISO/PAS 3930/OIML R99, surface temperature meter (±2 K accuracy between 323 K and 373 K), pulse revolution counter (specified rpm accuracy ranges), and ambient temperature meter (±2 K between 278 K and 313 K).
- Pre‑use checks & maintenance: Calibrate and zero/span check analysers (reference gases or electronic methods). Perform checks at start of day, when ambient conditions change, or at new test sites. Follow manufacturer and national maintenance schedules.
- Motorcycle preparation: Warm up per manufacturer. If unspecified: four‑stroke engines warmed until oil drain bolt head surface reaches 328–343 K; two‑stroke warmed by running ≥15 minutes or ~5 km in urban conditions. Ensure choke is off and exhaust system is leak‑proof.
- Sampling & measurement procedure: Insert sampling probe at least 600 mm into exhaust outlet (use extension if needed). For multiple outlets, combine or average outlets per the standard. Use the highest analyser scale, wait ≥15 s after probe insertion, measure for up to 30 s to obtain minimum and maximum values and report the arithmetic mean.
- Corrections & reporting: Measured values shall be corrected per national requirements; Annex B gives example correction formulas (including methods for engines with secondary air systems and separate two‑stroke/four‑stroke CO corrections). Presentation of results is specified in Annex A (test report fields, units, engine and analyser details).
Applications
- Vehicle inspection stations and official roadside enforcement for on‑site emissions checks.
- Repair shops and technicians for diagnostics and maintenance verification.
- Regulators and type‑approval authorities to define inspection protocols.
- Equipment manufacturers developing portable exhaust gas analysers and probes.
Keywords: ISO 17479:2013, motorcycle emissions measurement, gaseous exhaust emissions, idling condition, exhaust gas analyser, inspection, roadside checks.
Related standards
- ISO 3929 (road vehicles - similar inspection methods)
- ISO 3833 (vehicle definitions)
- ISO/PAS 3930 / OIML R99 (instruments for measuring vehicle exhaust emissions)