One big reason a lot of people choose to start riding a motorcycle is because of how fuel efficient they can be compared to other vehicles. Because motorcycles are much smaller, it doesn’t take much fuel to power them up and take them to wherever you need to go.
But sometimes a motorcycle can start getting bad gas mileage which is quite frustrating. That’s one of the biggest pros of having a motorcycle in the first place, so bad gas mileage on a vehicle like this almost makes the ride seem pointless.
Why is my motorcycle getting bad gas mileage? There are many reasons that could cause a motorcycle to get bad gas mileage, but the most common and obvious reasons could be that it’s running rich, there is a gas leak, the brakes are too tight, continuous high revs, and mostly riding your motorcycle on city roads rather than highways or freeways.
Though motorcycles are a little more simple compared to other vehicles, that doesn’t mean they’re immune to mechanical issues such as poor gas mileage. I’ve run into this problem many times myself and have been able to fix it through these troubleshooting skills I’ve learned.
What Causes Bad Gas Mileage
The first and most likely reason a motorcycle could be experiencing poor gas mileage is because it is running rich. That means that the fuel delivery system is delivering too much gas and not enough air into the combustion chamber of the engine. This can ultimately cause your motorcycle to waste a lot of fuel.
There are several symptoms you can look for if you suspect your motorcycle is running rich. If your motorcycle is sputtering, backfiring, or simply running poorly you may have an engine running rich. Other symptoms may include a strong smell of gas while the motorcycle is running, a flooded engine, and gas getting spewed out of the exhaust pipes.
There could be several culprits to a motorcycle running this way. You could possibly have stuck open floats in the carburetor, a sticking throttle needle, or malfunctioning spark plugs. To learn how to fix a motorcycle running rich, see my other article here.
If you know your motorcycle isn’t running rich but is still getting poor gas mileage, you’ll want to check for any gas leaks. Gas leaks can be a little tricky to detect because some of them only happen while the motorcycle is on and you’re not necessarily paying attention to it.
Gas leaks can be common among motorcycles, especially older ones. Gas leaks usually happen when a fuel line isn’t on tight enough or is brittle or when there is a faulty gasket somewhere in the carburetor.
Also, don’t discount the possibility of a small pin-hole that may have formed in the gas tank due to rust. Before taking your bike for a ride, turn it on and do a walk around to see if you notice any leaks or a strong smell of gas. Click here to see my complete list of why a motorcycle could be leaking gas.
Another possible culprit to bad mileage on your motorcycle could be tight brakes. It may not be as common, but if you recently installed new brake pads or fiddled with the braking system in anyway and now you have poor gas mileage, check in on the brakes again.
If the brakes are too tight, that’s putting a lot of back force on the engine which in turn has to work harder to get up to speed which uses more gas. You will be able to easily tell if this is your issue by taking your motorcycle for a spin, get up to a good speed, then letting off the throttle and letting the motorcycle coast. There shouldn’t be much of a lag or resistance.
Also pay attention to the way that your ride your motorcycle. High revs could cause bad gas mileage and it can do it quickly. If you like to show off and rev your motorcycle multiple times during your ride, you may want to back off a bit if you’re wanting to save some money on gas.
High revs can also be caused by the way you are shifting gears. Shifting gears too late means you’re waiting for a high RPM to shift and that can cause bad gas mileage. Try shifting gears at a lower RPM and see how your bike responds to it.
The last culprit to poor gas mileage on a motorcycle is city driving. Motorcycles get optimal miles per gallon on highways or freeways going around 50-60 miles per hour without having to stop all the time. Driving on city roads can greatly diminish your mileage because you’re constantly stopping and going at stop signs and red lights.
The Normal Gas Mileage A Motorcycle Should Get
Knowing whether or not your motorcycle is getting good gas mileage depends on your understand of what gas mileage your motorcycle should be getting in the first place. The average motorcycle gets around 35-40 miles per gallon.
It’s no wonder people resort to motorcycles for transportation with mileage like that. Anything less than that could simply mean that’s normal for the type of motorcycle you have and vice versa. Or there could be an underlying problem.
Understand that 35-40 miles per gallon is an average for motorcycles. Larger bikes such as touring motorcycles will get worse gas mileage because they have a lot more heavy equipment on them to make the rider a little more comfortable on their ride.
Tips For Increasing Gas Mileage
Aside from fixing any underlying issues that may be causing bad gas mileage on your motorcycle, there are a few other things you can do to help you save a few bucks when it comes to filling up at the pump.
It’s always a good idea to do regular maintenance on your motorcycle. Such maintenance may include regular oil changes and checking the tire pressure at regular intervals. Oil changes help maintain optimal engine health which in turn gives you better mileage.
Checking the tire PSI frequently can also help with your mileage. Having too low of a tire pressure means there’s more surface area touching the road which can lead to lagging. Click here to see my article about how often you should get your motorcycle serviced.
Using high quality gas can also help you get better gas mileage. It may seem like you’re defeating the purpose of good gas mileage by getting the “expensive” gas, but it still actually saves you a lot of money in the long run.
Whether you want to believe it or not, some of the more expensive gas stations that have additives (such as Techron) really does improve the performance of the engine. And when the engine improves it’s performance, that means you get better gas mileage.
You can also try being as aerodynamic as possible. This means giving the wind less of a chance to fight against the motorcycle. If there are any heavy accessories on your motorcycle that you don’t need, think about taking those off. You may also want to try a more aerodynamic helmet such as a full face helmet which has actually proven to help with gas mileage.
How To Calculate Motorcycle MPG
Low gas mileage on a motorcycle usually doesn’t require an equation to figure it out. If something is going on with your motorcycle, you’ll likely be able to tell because of how much more frequently you’ll need to fill up.
But it is always nice to have something to rely on in the case you are suspicious your mileage is decreasing. Luckily there is a very simple but very trusting equation you can use to calculate your gas mileage.
The equation goes like this: miles driven ÷ gallons fueled = gas mileage. For example, if you drove 130 miles since your last fill-up and you put in 3.8 gallons of gas into your tank, your gas mileage would be about 34.2 miles per gallon (130÷3.8=34.2).
This only works if you’re aware of how many miles you ride between filling up your tank. If this is something you’d like to consistently keep track of (which I recommend), carry a little notebook around with you and fill it out every time you go to a gas station. This is the best way to determine when your motorcycle is lacking on mileage.