World Motorcycle Test Cycle

The World Motorcycle Test Cycle (WMTC) is a system of driving cycles used to measure fuel consumption and emissions in motorcycles. The methods are stipulated as part of the Global Technical Regulation established under the United Nations’ World Forum for Harmonisation of Vehicle Regulations, also known as WP.29.

In the European Union, as in other legislative regions, precise limits for vehicle emissions are prescribed by law. However, exhaust emissions are inherently rather variable making it difficult to reliably reproduce test scores. The goal of these Test Cycles is to define, in detail, standardised driving cycles that can be performed using a finished vehicle (rather than an engine test rig) which can be used repeatedly with the expectation that consistent results will be produced. The driving cycles are intended to represent typical driving conditions.

For example, a motorcycle's wheels are placed in contact with a set of rollers which can be adjusted to simulate friction losses and aerodynamic resistance. The motorcycle is then accelerated and braked in a variety of patterns to represent a particular type of real-world operation. Therefore, statistical conclusions on pollutants emitted or fuel consumed by a variety of vehicles and testers (e.g. manufacturers) can be:

and for manufacturers

The specific drive cycles applied to motorcycles are labelled WMTC

For consumers, when a manufacturer quotes consumption, emission or other statistics referencing WMTC, they can be compared directly against other manufacturers also referencing WMTC. If a manufacturer does not reference this standard, then a consumer can only take on faith that the statistics offered are both representative and valid. Also, it seems the reliability of these (WMTC) tests might be accelerating the introduction of new technologies to reduce emissions and improve fuel economy - for the benefit of consumers.

These standards have emanated from within the EU under the auspices of the UNECE but their use worldwide is neither obligatory nor can they be enforced. However, in order to sell motorcycles within a regulated market, such as the European Union for example, manufacturers must meet WMTC emission standards which means effectively they must also adopt these test cycles.

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