Cars 'cleaner and greener' than bikes

The age old debate of cars versus bikes usually centres on performance - and motorcycles usually win due to their power-to-weight ratios - but what about exhaust emissions?

One of television's most popular science shows, Mythbusters, has proved that motorcycles are not as green or clean as cars.

Due to their light weight and small engines (compared to cars), motorcycles have generally been considered more efficient, and also cleaner and greener, but according to Jamie Hyneman and Adam Savage of the Mythbusters series, the clean and green bit is not so clear cut.

Two expert groups were brought in to help bust the myth that bikes are cleaner running than cars: Global MRV (Measure, Report, and Verify), a vehicle performance measurement company, and CE-CERT, the Centre for Environmental Research and Technology, which is part of the University of California.

David Miller, Global MRV's Chief Tech Officer (Clean Air Tech Division) supplied the portable emissions measurement system (PEMS), while CE-CERT's Dr. Kent Johnson, an assistant research engineer, joined the investigation as a third-party analyst, to basically make sure all the research data made sense.

The test took three days to complete and was thus: three cars and three motorcycles, one each from the 1980s, 1990s and 2000s, were tested to see the sort of emissions that resulted. It is unclear what the criteria was for choosing vehicles, but the emissions tested for were:

To cut a long story short, motorcycles didn't perform as cleanly as cars.

Though the findings are unlikely to result in an overhaul of emission restrictions on motorcycles - which are beneficial in other ways, such as reducing traffic congestion and impact on the road infrastructure - the findings will certainly give anti-motorcycle lobbyists another point with which to argue.

More details and official videos can be found at the official Mythbusters website.