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Can You Run E85 In A Harley Davidson?

There are many fuel types, and finding one that best fits your vehicle is essential for peak performance. So, can you fuel up your Harley Davidson with E85 fuel? We've done the work to bring you the answer.

Yes, your Harley Davidson can run on E85 fuel consistently (with the proper tuning and modifications). E85 or flex fuel primarily consists of ethanol with a bit of energy mixed in; it can give a vehicle a power boost if its components support it.

Knowing what fuel your vehicle can take in is essential since this can boost the performance of your motorcycle or ruin the bike completely. For more information about Harleys and vehicle fuel, keep reading below.

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Harley Davidson motorcycle black, Can You Run E85 In A Harley Davidson?

Running E85 In A Harley Davidson

Though it is still best to use the recommended fuel for your Harley Davidson, which is pure unleaded fuel, you can sometimes run pure E85. Remember, running E85 on your motorcycle without any preparation and the correct components can lead to faster wear and may even break your engine.

E85 is a mixture of roughly 85% ethanol and 15% gasoline, with "E" for ethanol and "85" for the ethanol percentage. E85 is cheaper than regular gasoline, but only some cars and motorcycles can run this. Since E85 has a higher octane of around 100 to 105, it can boost your vehicle.

Typically with an E85, you'll have less range for your vehicle, but this should be fine since deciding to go E85 means you want to push out more power. The difficulty of tuning and modifying all Harley Davidsons to E85 will differ.

It is best to use E85 with performance in mind, so if you don't want to go fast or race your motorcycle, it's ideal to keep using premium fuel. Again, to be safe, it is best to use premium unleaded fuel if your bike is not modified to take in E85 to prevent the risk of any wear.

Woman hand close up tucking a Harley Davidson motorcycle at a gas station. old gas station in Crevier on the road to Ottawa from Mon

Do You Get Better Gas Mileage With E85?

Fuel gauge with a red needle indicating empty. 3d render

Getting exceptional mileage is a great feature to have on your car. If your vehicle has excellent gas mileage, you can travel more without topping off with fuel, saving you money.

Motorbikes are known for their great mileage, but not all bikes are the same since they have different engine designs. But in the case of most Harleys, they aren't known for their great mileage compared to other bikes.

Now, will switching to E85 give your Hayley Davidson better gas mileage? The short answer is no; E85 will not provide your bike with better gas mileage. This fuel has a low energy content since it mainly consists of ethanol.

You can expect a 27% to 30% difference in the mileage of premium unleaded and E85, with E85 always being lower. Though E85 does not help increase the mileage of your car, it does help boost performance since this fuel burns faster.

In short, you would want to use E85 as a performance booster rather than a fuel saver. Even if E85 is cheaper, you'll find yourself refueling much more, which will cost you more in the long run.

Check out this video to see what it's like to travel with E85 on a vehicle—

How Long Can You Store E85?

Green jerry can close-up on blurred background of garages

Storing fuel is essential, especially if your area does not have the specific fuel you need. Since only some people use E85, some gas stations may not offer it.

One important thing to remember is that E85 absorbs water, significantly affecting the fuel's usability. It would be best to use a metal container since E85 could eat plastic containers. Ethanol-based fuel will have a shorter life compared to regular and premium fuel.

You can keep E85 from a few weeks to a year, depending on how well the fuel is stored. A fully sealed metal container will ensure that moisture won't mix with the fuel, greatly extending the fuel's life.

Check out this metal gas can on Amazon.

You'll know when your fuel is going bad when you stall, have difficulty starting, water builds up on the bottom of the container, or there's a reduced amount of gas in the storage container (this means condensation has occurred).

What Is The Difference Between Regular And Premium Fuel?

Gasoline octane selection buttons at a typical self service gas station.

The main difference between regular and premium pump fuel is the level of octane it contains. With regular fuel, you are looking at an octane level of 87; with premium fuel, you are looking at 91 or higher.

The octane rating measures how well the gas can resist "knocking" during combustion. Knocking can happen when you put regular fuel into a vehicle that requires premium fuel. If the octane rating is too low, it may combust too early.  

Cars and motorcycles with higher compression ratios need premium fuel since this will help them work correctly. Using regular fuel on these types of vehicles will affect the overall performance.

In the US, the typical premium fuel you'll find is 91 or 93. You may find premium fuel labeled as "Ultra" or "Super-Premium." When you get a vehicle, the user manual will state what fuel you should use; use the recommended fuel to ensure your vehicle will perform as intended.

Most modern cars and motorcycles require you to use premium fuel because of the higher octane rating; this fuel typically gives the vehicle more power. At the same time, older cars and motorcycles can both use regular and premium.

Unlike diesel and gas mixing up, putting regular fuel into a vehicle that needs premium and vice versa will not permanently damage it. Also, don't use E85 as an alternative since some gas stations offer this with the label "Premium."

E85 is an ethanol-based fuel and is only for modified and tuned vehicles to take it in. Even though it may have the same properties and even higher octane levels, running your vehicle with pure ethanol without proper preparation will damage it.

Can A Motorcycle Run On Diesel?

Black plastic cap of aluminum gas tank in silver color with the inscription DIESEL

No, you cannot fuel up your motorcycle with diesel. Putting diesel on your bike can stall or damage the engine, which will be costly. Most motorcycles seen on the road today use gasoline.

Even when you are out of fuel, it is never a good idea to use diesel as a substitute; you can use regular gas but use only enough to get you home, and after that, drain it out. Using premium fuel (as stated by the motorcycle's user handbook) will ensure your bike runs at peak performance.

So before you start pumping fuel into your motorcycle, make sure it's not diesel. It is better to take your time to ensure you have the correct fuel than to fix your bike.

Are There Diesel Bikes?

Female's gentle hand is holding a fueling gun. Motorcycle's tank is fueling by female owner

Yes, a handful of diesel bikes made it out into the market, but they may be hard to get since these are old models. These diesel bikes may still exist, but they may only be road legal with the proper modifications to pass inspection.

The Royal Enfield Taurus and the Hayes M1030 military diesel motorbike are the most notable diesel bikes. Both these bikes are likely to be rare in the US since the Royal Enfield Taurus is only available for the Indian market and the Hayes M1030 is a military bike.

Diesel engines are a great choice on paper since they are durable, have fewer moving parts, have a higher torque number, and are more fuel efficient than gasoline. Bikes like the Royal Enfield Taurus typically get 200 miles per gallon, and its fuel tank can hold up to 4 gallons.

In Closing

Harley Davidson motorcycle black

You can put E85 in your Harley Davidson, but only if you have prepared the bike; you need a tune and the right components unless you will use your vehicle for the track or get more power; it's best to stick to premium unleaded fuel. Your motorcycle may stall or even break some components if you use E85 without preparation.

Don't use any other fuel but unleaded gasoline for your motorcycle. There are no motorcycles on the market currently with diesel engines. If you need a quick refuel, use regular gas to get you going again.

For more automotive topics and tips, check out the following posts—

Why Won't My Harley Davidson Start When Hot?

Can You Get A Motorcycle License Without A Driver's License?