Archive · 16 Nov 2025
Study Links Two-Wheeler Emissions to Mileage, Urges Scrappage Policy Overhaul
Imagine your scooter or motorcycle.
A new study looked at the smoky air that comes out of their pipes, especially when they're just sitting and running, not moving.
They found that older bikes and bikes that have traveled many miles release more pollution, like carbon monoxide.
This is because as bikes get older, their engines and the parts that clean up the exhaust don't work as well.
The study suggests that when the government decides to take old bikes off the road, they should consider how many miles the bike has been ridden, not just how old it is.
This could help make the air cleaner.
A study found that both the age of a two-wheeler and its mileage significantly impact carbon monoxide (CO) and hydrocarbon (HC) emissions.
Researchers from Delhi Technological University analyzed data from 575 BS III and BS IV-compliant petrol two-wheelers in Delhi.
The study indicates that age accounts for 84.6% of the change in CO levels and 81.5% of the change in HC levels.
The current Indian scrappage policy, which relies solely on vehicle age, needs to be revised to include mileage as a key factor.
The study recommends an upgraded emission certification system that considers real-world loaded operations beyond just idling measurements.
- Who
- Researchers from Delhi Technological University, in collaboration with Jacobs Engineering Group and the University of Chemistry & Technology, Prague
- What
- A study found that vehicle age and mileage significantly impact carbon monoxide (CO) and hydrocarbon (HC) emissions from two-wheelers in India, recommending an overhaul of the current age-based scrappage policy to include mileage.
- When
- The study analyzed real-time exhaust data, and its findings were published recently.
- Where
- Delhi, India
- Why
- To examine the factors influencing exhaust emissions from two-wheelers and suggest improvements to emission certification and vehicle scrappage policies.
- Study Focus
- Exhaust emissions from two-wheelers in India
- Key Findings
- Vehicle age and mileage strongly influence CO and HC emissions
- Vehicles Analyzed
- 575 BS III and BS IV-compliant petrol two-wheelers
- Institutions Involved
- Delhi Technological University, Jacobs Engineering Group, University of Chemistry & Technology, Prague
- Primary Recommendation
- India's scrappage policy should include mileage, not just age