What is the emission standard for motorcycles?

[HectorAnn]

Motorcycle emission standards should comply with the China IV emission standard. Below is a relevant introduction to the China IV emission standard: Introduction: The China IV emission standard is the national fourth-stage motor vehicle pollutant emission standard. The main pollutants emitted by vehicles include HC (hydrocarbons), NOx (nitrogen oxides), CO (carbon monoxide), PM (particulate matter), etc. Through the application of technologies such as improved catalytic converter active layers, secondary air injection, and exhaust gas recirculation systems with cooling devices, the standard aims to control and reduce vehicle emissions to below specified limits. Standard values: The emission limit for hydrocarbons is below 0.1 grams per kilometer, for carbon monoxide below 1.0 grams per kilometer, for nitrogen oxides below 0.08 grams per kilometer, with no requirements for particulate matter.

[Eleanor]

I've been riding motorcycles for several years. The emission standards for motorcycles mainly depend on where you buy them. Currently, China implements the National IV standard, which was fully rolled out in 2019. Simply put, it requires new motorcycles to be equipped with electronic fuel injection systems, and carbon monoxide emissions must not exceed 1 gram per kilometer. In the previous National III era, carburetor motorcycles were still allowed, with a carbon monoxide limit of 5 grams, causing much more pollution. In fact, National IV motorcycles are more fuel-efficient, last longer with proper maintenance, and their exhaust is less pungent. The EU uses the Euro 5 standard, which is slightly stricter than ours, with a nitrogen oxide limit of 0.06 grams. I heard that China might upgrade to National VI by 2025, which would definitely be good for air quality. When choosing a motorcycle, pay attention to the environmental label and avoid older used models, as they could be restricted from use at any time. Regularly changing air filters and engine oil can also help reduce emissions.

[VonHenry]

A buddy who works on motorcycle repairs mentioned that emission standards have a significant impact on engine technology. The China IV standards mandated the replacement of carburetors with electronic fuel injection and added OBD diagnostic systems, allowing the vehicle's computer to monitor exhaust emissions in real time. For example, the carbon monoxide emission limit for carbureted bikes was 5g/km, but under China IV, it dropped to 1g/km, with nitrogen oxides also capped below 0.15g. The EU's Euro 5 standards are even stricter, limiting it directly to 0.06g/km. Nowadays, China IV-compliant vehicles require three-way catalytic converters with over 90% efficiency, while older models are prone to clogging and failure. During repairs, it's been observed that compliant vehicles have less carbon buildup and run more stably over time. Modifying the exhaust pipe might trigger alarms and cause the vehicle to fail annual inspections. The new regulations are pushing manufacturers to upgrade their tech—higher costs, but worth it for the environment.

[OSarah]

Motorcycle emission standards are implemented in phases, with China III introduced in 2008 and succeeded by China IV in 2019. Key differences: For China III carburetor motorcycles, the CO emission limit was 5.0g/km, which was reduced to 1.0g/km after switching to electronic fuel injection under China IV. The NOx limit decreased from 0.3g to 0.15g/km. China IV added an OBD system to monitor exhaust emissions, and exhaust pipes must be equipped with high-efficiency catalytic converters. The EU implements Euro 5 standards with a stricter NOx limit of 0.06g/km. China IV vehicles produce half as much pollution during cold starts and are more effective in controlling PM2.5. Beijing tests show China IV motorcycles reduce emissions by over 30% compared to China III. When buying a new vehicle, check the environmental compliance list to verify the standard version.

[OBrady]

From a technical perspective, motorcycle emissions are categorized into China III and China IV stages. China III permits carburetors with a CO emission limit of 5g/km; China IV mandates full electronic fuel injection, reducing the same indicator to 1g/km and capping nitrogen oxides at 0.15g/km. Most crucially, China IV requires compulsory installation of OBD systems, essentially equipping motorcycles with a 'black box' for real-time exhaust monitoring. Catalytic converter efficiency must exceed 90%, making older vehicles prone to failing due to carbon deposit accumulation. The EU's Euro 5 standard sets nitrogen oxide limits at just 0.06g/km. Compliant new models experience minimal horsepower loss while achieving approximately 10% long-term fuel consumption reduction. Regular throttle body cleaning is recommended to prevent emission degradation.

[PiperDella]

Motorcycle emissions in China follow the national standards, such as China IV limiting carbon monoxide to 1.0g/km and nitrogen oxides to 0.15g/km; the EU Euro 5 is stricter, with nitrogen oxides limited to 0.06g/km. China IV vehicles must use electronic fuel injection and OBD systems, with catalytic converter efficiency above 90%. Older China III vehicles had a carbon monoxide limit of 5g/km and are now mostly phased out. For regular owners, buying a China IV-labeled vehicle makes annual inspections easier and offers lower fuel consumption. Some believe European standards are more advanced, but China IV technology is sufficient. Frequent air filter changes during maintenance help prevent excessive emissions. Future China VI standards may align with European standards, so those interested in vintage cars should consider collecting them sooner.