GB 19758-2005Limits and measurement methods for exhaust smoke emissions from motorcycles and mopeds (English PDF)

3.1 Motorcycles and mopeds

Motorcycle: A two-wheeled or three-wheeled motor vehicle that is equipped with a spark ignition engine, with weight of entire vehicle smaller than 400kg, engine capacity larger than

50ml or maximum designed speed larger than 50km/h.

Moped: A two-wheeled or three-wheeled motor vehicle that is equipped with a spark ignition engine, with weight of entire vehicle smaller than 400kg, engine capacity not more than 50ml or maximum designed speed not more than 50km/h.

3.2 opacity N (%)

Opacity refers to the ratio of the light emitted by the light source that cannot pass through the smoke exhaust, expressed as a percentage. It is 0% when the light is completely transmitted, and 100% when it is not transmitted at all.

3.3 effective optical path length L (m)

Effective optical path length refers to the length of the light beam crossed by the smoke exhaust between the light source and the light-receiving element. This length has been corrected for the inhomogeneity caused by density gradients and edge effects.

5.1.3 Before the test, the vehicle under inspection must be subjected to running-in in accordance with the stipulations of the enterprise’s product instruction manual. If the manufacturer agrees, the vehicle under inspection may be exempted from the running-in.

5.1.4 In accordance with the measurement method in Appendix A, carry out the type approval test of exhaust smoke emission of motorcycles and mopeds.

5.1.5 For the application for type approval and the extension of type approval, refer to the relevant clauses in GB 14622.

5.2 Production Conformity Inspection Test

Production conformity inspection test refers to the test of inspecting the exhaust smoke emission of motorcycles and mopeds produced in batches by manufacturing enterprises.

5.2.1 For batches of motorcycles and mopeds that have passed the type approval test under this

Standard and have been approved for production, all parts that affect the exhaust smoke of the engine shall be consistent with those of the sample vehicles that have undergone the type approval test.

5.2.2 In order to verify the consistency specified in 5.2.1, a sample vehicle shall be taken from the mass-produced products.

5.2.3 In accordance with the stipulations of 5.1.3, conduct the running-in.

5.2.4 In accordance with the measurement method in Appendix A, conduct a production

conformity inspection test on the exhaust smoke emission of motorcycles and mopeds.

5.2.5 To judge whether the mass-produced products are qualified or not, refer to 6.3.2 in GB

14622.

5.3 In-use Vehicle Inspection Test

In-use vehicle inspection test refers to the inspection test of exhaust smoke emission of motorcycles and mopeds with registered license plates.

5.3.1 By means of visual inspection and test run, check whether the parts and engines of motorcycles and mopeds are normally operating, and it is allowed to adjust or replace parts.

5.3.2 In accordance with the measurement method in Appendix A, conduct the in-use vehicle inspection test on the exhaust smoke emission of motorcycles and mopeds.