Motorcycles Are Great on Gas, but Are They Bad for the Planet?

Have you ever thought about the environmental impact of riding your fuel-sipping motorcycle versus your gas-hog pickup? The reality of motorcycle emissions might come as a surprise.

It’s game day and your buddy has an extra ticket to the Egg Bowl. If you leave in the next 15 minutes, you can make kickoff — you just need to crush 5 hours of highway pavement. Do you take your BMW R1150GS or your shiny new RAM 1500 HFE pickup?

Your weather app shows 92 degrees, and it’s humid like a Finnish sauna, but you’re feeling eco-conscious and opt for the GS at 37 mpg. You make the game just in time. By now, you look like you took a sweat shower with your clothes on, and have zero chance of cozying up to any of the Bulldog cuties.

The saddest part? You did no favors for the planet; that 500-pound GS actually spews out more harmful chemicals than your 5,000-pound truck.

Too bad. The few bucks you saved on gas won’t even buy you a beer at stadium prices. But the emissions data about your motorcycle is no joke.

Tailpipe Wars

Over the past two decades, passenger vehicle emission systems have improved dramatically. This has been driven by CAFE regulations in the U.S. and the Euro-6 in the EU. Modern engine control and closed-loop catalytic exhaust systems can eliminate many harmful greenhouse gasses (GHGs). Motorcycles make up the smallest fraction of transportation — less than 1% in the U.S. — so they’re not targeted for regulation like cars.

Sure, you say, but the exhaust volume from 1,150cc is far less than from a 3.6 L V6. You’re right. The problem is not the quantity of exhaust but the quality.

The gas volume that comes out of your tailpipe is largely benign, but the culprits — CO2, CO, HC, and NOx — are what we care about. These gases are what damage the atmosphere. Catalytic systems can capture most GHGs, but the existing technology is too large and restrictive to implement on motorcycles.

Motorcycle Emissions vs. Automobile Emissions

Before any new car hits the showroom, the EPA runs an emissions evaluation and calculates a “CO2 equivalent” — a single number representing GHGs CO2, NO X, HC, and CO. The CO2 equivalent units are in grams per mile (g/mile), so a higher number means more GHGs and more climate damage.

For a 2WD 2020 RAM 1500 HFE on the highway, that number is 340 g/mile. Unfortunately, motorcycle emissions data isn’t documented by the EPA. This is a real issue because if the problem isn’t measured, you don’t know what to fix.

There are a few independent studies that shed light on the issue, however. One published in 2008 by Swiss researchers took real data from several motorbikes, including a BMW R1150GS.

The GS highway CO2 equivalent is a stunning 380 g/mile (17% worse than the RAM truck). They found that a 1993 Honda Shadow VX600 with only 583 ccs spews a whopping 408 g/mile. That is twice as much as a new Honda Civic.

Other studies would suggest the problem is even worse. Global MRV tested out its portable emissions equipment in 2011 comparing 12 motorcycles to 12 cars of varying years — this was featured on an episode of “Mythbusters.”. Motorcycles were almost universally terrible, with motorbikes from the 2000s producing 3,220% more NOx and 8,065% more CO2 than cars of the same era.

Motorcycle Emissions Data

In 2008, the L.A. Times reported that while motorcycles accounted for 1% of all miles traveled, they were responsible for 10% of the state’s smog-producing emissions.

Useful as they are, these studies are a decade old. In the years since then, “Euro-5” standards in Europe and US EPA “Tier 3” have placed more stringent controls on moto emissions.

While there still isn’t much hard data from the EPA, there are new tools to estimate CO2e. We tried the carbon calculators at ThrustCarbon.com, YourFootPrint.app, and TryCarbonAPI.com and found numbers between 180 g/mi and 320 g/mi for “large” motorcycles. On average, that’s a 40% improvement since 2008 — far less than a RAM truck but still dirtier than a Ford Fiesta!

California has the largest motorcycle ridership in the country and some of the best data. All new engines introduced to the state must pass emissions testing — and that data is publicly available. Unfortunately, CO2e data isn’t captured. We can look at the improvement in H+NOx emissions as an indicator, however. We pulled numbers for three 1,000cc sport bikes from Yamaha, Suzuki, and Kawasaki.

Between 2008 and 2022, emissions fell by about half! While that sounds like great news, the volume of GHGs from motorbikes in California has remained largely unchanged, which can only mean that more people are riding more miles on motorcycles.

Environmental Impact: Not Just About Emissions

There’s more to being green than GHGs. It’s important to consider the total environmental footprint of your transportation. Motorcycles can be less energy-intensive to produce than automobiles, as they’re much smaller and simpler. This does depend on the bike and car in question, as small production volumes don’t have the same efficiencies of scale as high-volume cars.

One other overlooked pollutant is particulate matter. Particulate matter is generated by a combination of tailpipe emissions, brake dust, and tire wear.

Being smaller means motos generate less particulate matter than cars. Less mass means less brake dust and rubber wear. That also means that a Piaggio is a greener choice than a Panigale, and burnouts are a bad idea.

Zero Motorcycle Emissions

If you want to keep your Greenpeace membership and still shred, full electric is the only way to go. Lucky for us, electric motorcycles are also starting to get really exciting.

If the Harley Livewire or Zero DSR/X don’t trip your trigger, then check out Energica. These bikes are true stallions worthy of the Italian flag with the racing heritage to back up their street cred.

Going Green: The Moto or the Auto?

The bike versus automobile environmental impact question doesn’t have a simple answer. There are just too many variables.

For example, if your route to the game was through downtown Memphis the GS might win since the pickup isn’t efficient in slower stop-and-go situations. What is truly needed is more data from real-world tests and carbon footprint auditing.

By starting to measure the problem, we can target the changes that will make a difference. Until then, don’t feel bad about jumping in the cab and cranking the AC if you need to arrive looking fresh for that cutie.

Pure electric is the best technology we currently have for reducing motorcycle emissions. While nothing tugs at my heartstrings like the sound of a V-twin and dry clutch, silent electric propulsion is nothing short of exhilarating. If you haven’t yet, go experience the thrill of burning electrons instead of petrol.

Lastly, dear reader, let’s be real here. Deep down, you don’t care about any of this. Motos are passion first and practicality second for most of us in North America and Europe.

Also, #motodistancing is much-needed throttle therapy. Seriously, why are you still reading? Go put the fun between your legs!

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