Octane or Ethenol
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Outstanding HDF Member
Joined: Jun 2010
Posts: 2,015
Likes: 3
From: Moline, IL
Octane or Ethenol
i try to always run the higher octane gas in my bike and w/o ethenol. the problem im running into lately around here is the stations have the following 3 option
1) 87 octane w/o ethenol
2) 89 octane w ethenol
3) 91 or 93 (depends on station) w/ ethenol.
i try to get it where 91 or 93 w/o is an option but cant always
what your guys opinion here? is it better to have lower octane to keep from having ethenol or run ethenol so i can have the higher octane?
1) 87 octane w/o ethenol
2) 89 octane w ethenol
3) 91 or 93 (depends on station) w/ ethenol.
i try to get it where 91 or 93 w/o is an option but cant always
what your guys opinion here? is it better to have lower octane to keep from having ethenol or run ethenol so i can have the higher octane?
Road Warrior
Joined: Nov 2010
Posts: 1,870
Likes: 4
From: Jacksonville, FL
Do what the manufacturer suggests, they built it and warranty it. If you don't want to read it, 91 Octane (or better) and 10% or less Ethanol. Also remember, you are running an Air/Oil/Fuel cooled engine, all 3 of those figure into your engines cooling ability. The lower the Octane rating, the more likely it is to pre-detonate in high heat (aka, an air cooled engine) and that can cause engine damage.
Straight from the Owners Manual...
Gasoline Blends
Your motorcycle was designed to get the best performance and efficiency using unleaded gasoline. Most gasoline is blended with alcohol and/or ether to create oxygenated blends. The type and amount of alcohol or ether added to the fuel is important.
Do not use gasoline that contains methanol. Doing so can result in fuel system component failure, engine damage and/or equipment malfunction. (00148a)
Gasoline containing METHYL TERTIARY BUTYL ETHER (MTBE): Gasoline/MTBE blends are a mixture of gasoline and as much as 15% MTBE. Gasoline/MTBE blends can be used in your motorcycle.
ETHANOL fuel is a mixture of ethanol (Grain alcohol) and unleaded gasoline. While ethanol does have an impact on fuel mileage, fuels with an ethanol content of up to 10% may be used in your motorcycle without affecting vehicle performance. U.S. EPA regulations currently indicate that fuels with 15% ethanol (E15) are restricted from use in motorcycles at the time of this publication. Motorcycles delivered in some countries are calibrated to operate with higher ethanol concentrations to meet the fuel standards in those countries.
REFORMULATED OR OXYGENATED GASOLINES (RFG): Reformulated gasoline is a term used to describe gasoline blends that are specifically designed to burn cleaner than other types of gasoline, leaving fewer tailpipe emissions. They are also formulated to evaporate less when you are filling your tank. Reformulated gasolines use additives to oxygenate the gas. Your motorcycle will run normally using this type of gas and Harley-Davidson recommends you use it when possible, as an aid to cleaner air in our environment.
Do not use race gas. Use of these fuels will damage the fuel system.
Harley-Davidson recommends using SCREAMIN' EAGLE SUPER OCTANE BOOST to raise fuel octane. This is the only octane booster that has been extensively tested and approved for use with Harley-Davidson engines and components.
Some gasoline blends might adversely affect the starting, driveability or fuel efficiency of the motorcycle. If any of these problems are experienced, try a different brand of gasoline or gasoline with a higher octane blend.
Fuel
Always use a good quality unleaded gasoline. Octane ratings are usually found on the pump. Refer to Octane Ratings.
Avoid spills. Slowly remove filler cap. Do not fill above bottom of filler neck insert, leaving air space for fuel expansion. Secure filler cap after refueling. Gasoline is extremely flammable and highly explosive, which could result in death or serious injury. (00028a)
Use care when refueling. Pressurized air in fuel tank can force gasoline to escape through filler tube. Gasoline is extremely flammable and highly explosive, which could result in death or serious injury. (00029a)
Modern service station pumps dispense a high flow of gasoline into a motorcycle fuel tank making air entrapment and pressurization a possibility.
Octane Ratings
SPECIFICATION RATING
Pump Octane (R+M)/2
91 (95 RON)
Straight from the Owners Manual...
Gasoline Blends
Your motorcycle was designed to get the best performance and efficiency using unleaded gasoline. Most gasoline is blended with alcohol and/or ether to create oxygenated blends. The type and amount of alcohol or ether added to the fuel is important.
Do not use gasoline that contains methanol. Doing so can result in fuel system component failure, engine damage and/or equipment malfunction. (00148a)
Gasoline containing METHYL TERTIARY BUTYL ETHER (MTBE): Gasoline/MTBE blends are a mixture of gasoline and as much as 15% MTBE. Gasoline/MTBE blends can be used in your motorcycle.
ETHANOL fuel is a mixture of ethanol (Grain alcohol) and unleaded gasoline. While ethanol does have an impact on fuel mileage, fuels with an ethanol content of up to 10% may be used in your motorcycle without affecting vehicle performance. U.S. EPA regulations currently indicate that fuels with 15% ethanol (E15) are restricted from use in motorcycles at the time of this publication. Motorcycles delivered in some countries are calibrated to operate with higher ethanol concentrations to meet the fuel standards in those countries.
REFORMULATED OR OXYGENATED GASOLINES (RFG): Reformulated gasoline is a term used to describe gasoline blends that are specifically designed to burn cleaner than other types of gasoline, leaving fewer tailpipe emissions. They are also formulated to evaporate less when you are filling your tank. Reformulated gasolines use additives to oxygenate the gas. Your motorcycle will run normally using this type of gas and Harley-Davidson recommends you use it when possible, as an aid to cleaner air in our environment.
Do not use race gas. Use of these fuels will damage the fuel system.
Harley-Davidson recommends using SCREAMIN' EAGLE SUPER OCTANE BOOST to raise fuel octane. This is the only octane booster that has been extensively tested and approved for use with Harley-Davidson engines and components.
Some gasoline blends might adversely affect the starting, driveability or fuel efficiency of the motorcycle. If any of these problems are experienced, try a different brand of gasoline or gasoline with a higher octane blend.
Fuel
Always use a good quality unleaded gasoline. Octane ratings are usually found on the pump. Refer to Octane Ratings.
Avoid spills. Slowly remove filler cap. Do not fill above bottom of filler neck insert, leaving air space for fuel expansion. Secure filler cap after refueling. Gasoline is extremely flammable and highly explosive, which could result in death or serious injury. (00028a)
Use care when refueling. Pressurized air in fuel tank can force gasoline to escape through filler tube. Gasoline is extremely flammable and highly explosive, which could result in death or serious injury. (00029a)
Modern service station pumps dispense a high flow of gasoline into a motorcycle fuel tank making air entrapment and pressurization a possibility.
Octane Ratings
SPECIFICATION RATING
Pump Octane (R+M)/2
91 (95 RON)
Last edited by edpnjax; Aug 16, 2013 at 10:36 AM.
Stellar HDF Member
Joined: Aug 2012
Posts: 2,134
Likes: 1,871
From: Minnesota
I agree with the above posts with one exception, the last couple tanks in the fall I would try to fill it with ethanol free gas due to the short shelf life of ethanol. Then if you cant get higher octane add an octane booster and seafoam to the last couple tanks before parking it (unless you have the luxury of riding year round like some of the folks down south)
Road Warrior
Joined: Nov 2010
Posts: 1,870
Likes: 4
From: Jacksonville, FL
I agree with the above posts with one exception, the last couple tanks in the fall I would try to fill it with ethanol free gas due to the short shelf life of ethanol. Then if you cant get higher octane add an octane booster and seafoam to the last couple tanks before parking it (unless you have the luxury of riding year round like some of the folks down south)
Road Master
Joined: Jan 2009
Posts: 773
Likes: 11
From: Roanoke, VA
Do what the manufacturer suggests, they built it and warranty it. If you don't want to read it, 91 Octane (or better) and 10% or less Ethanol. Also remember, you are running an Air/Oil/Fuel cooled engine, all 3 of those figure into your engines cooling ability. The lower the Octane rating, the more likely it is to pre-detonate in high heat (aka, an air cooled engine) and that can cause engine damage.
Straight from the Owners Manual...
Gasoline Blends
Your motorcycle was designed to get the best performance and efficiency using unleaded gasoline. Most gasoline is blended with alcohol and/or ether to create oxygenated blends. The type and amount of alcohol or ether added to the fuel is important.
Do not use gasoline that contains methanol. Doing so can result in fuel system component failure, engine damage and/or equipment malfunction. (00148a)
Gasoline containing METHYL TERTIARY BUTYL ETHER (MTBE): Gasoline/MTBE blends are a mixture of gasoline and as much as 15% MTBE. Gasoline/MTBE blends can be used in your motorcycle.
ETHANOL fuel is a mixture of ethanol (Grain alcohol) and unleaded gasoline. While ethanol does have an impact on fuel mileage, fuels with an ethanol content of up to 10% may be used in your motorcycle without affecting vehicle performance. U.S. EPA regulations currently indicate that fuels with 15% ethanol (E15) are restricted from use in motorcycles at the time of this publication. Motorcycles delivered in some countries are calibrated to operate with higher ethanol concentrations to meet the fuel standards in those countries.
REFORMULATED OR OXYGENATED GASOLINES (RFG): Reformulated gasoline is a term used to describe gasoline blends that are specifically designed to burn cleaner than other types of gasoline, leaving fewer tailpipe emissions. They are also formulated to evaporate less when you are filling your tank. Reformulated gasolines use additives to oxygenate the gas. Your motorcycle will run normally using this type of gas and Harley-Davidson recommends you use it when possible, as an aid to cleaner air in our environment.
Do not use race gas. Use of these fuels will damage the fuel system.
Harley-Davidson recommends using SCREAMIN' EAGLE SUPER OCTANE BOOST to raise fuel octane. This is the only octane booster that has been extensively tested and approved for use with Harley-Davidson engines and components.
Some gasoline blends might adversely affect the starting, driveability or fuel efficiency of the motorcycle. If any of these problems are experienced, try a different brand of gasoline or gasoline with a higher octane blend.
Fuel
Always use a good quality unleaded gasoline. Octane ratings are usually found on the pump. Refer to Octane Ratings.
Avoid spills. Slowly remove filler cap. Do not fill above bottom of filler neck insert, leaving air space for fuel expansion. Secure filler cap after refueling. Gasoline is extremely flammable and highly explosive, which could result in death or serious injury. (00028a)
Use care when refueling. Pressurized air in fuel tank can force gasoline to escape through filler tube. Gasoline is extremely flammable and highly explosive, which could result in death or serious injury. (00029a)
Modern service station pumps dispense a high flow of gasoline into a motorcycle fuel tank making air entrapment and pressurization a possibility.
Octane Ratings
SPECIFICATION RATING
Pump Octane (R+M)/2
91 (95 RON)
Straight from the Owners Manual...
Gasoline Blends
Your motorcycle was designed to get the best performance and efficiency using unleaded gasoline. Most gasoline is blended with alcohol and/or ether to create oxygenated blends. The type and amount of alcohol or ether added to the fuel is important.
Do not use gasoline that contains methanol. Doing so can result in fuel system component failure, engine damage and/or equipment malfunction. (00148a)
Gasoline containing METHYL TERTIARY BUTYL ETHER (MTBE): Gasoline/MTBE blends are a mixture of gasoline and as much as 15% MTBE. Gasoline/MTBE blends can be used in your motorcycle.
ETHANOL fuel is a mixture of ethanol (Grain alcohol) and unleaded gasoline. While ethanol does have an impact on fuel mileage, fuels with an ethanol content of up to 10% may be used in your motorcycle without affecting vehicle performance. U.S. EPA regulations currently indicate that fuels with 15% ethanol (E15) are restricted from use in motorcycles at the time of this publication. Motorcycles delivered in some countries are calibrated to operate with higher ethanol concentrations to meet the fuel standards in those countries.
REFORMULATED OR OXYGENATED GASOLINES (RFG): Reformulated gasoline is a term used to describe gasoline blends that are specifically designed to burn cleaner than other types of gasoline, leaving fewer tailpipe emissions. They are also formulated to evaporate less when you are filling your tank. Reformulated gasolines use additives to oxygenate the gas. Your motorcycle will run normally using this type of gas and Harley-Davidson recommends you use it when possible, as an aid to cleaner air in our environment.
Do not use race gas. Use of these fuels will damage the fuel system.
Harley-Davidson recommends using SCREAMIN' EAGLE SUPER OCTANE BOOST to raise fuel octane. This is the only octane booster that has been extensively tested and approved for use with Harley-Davidson engines and components.
Some gasoline blends might adversely affect the starting, driveability or fuel efficiency of the motorcycle. If any of these problems are experienced, try a different brand of gasoline or gasoline with a higher octane blend.
Fuel
Always use a good quality unleaded gasoline. Octane ratings are usually found on the pump. Refer to Octane Ratings.
Avoid spills. Slowly remove filler cap. Do not fill above bottom of filler neck insert, leaving air space for fuel expansion. Secure filler cap after refueling. Gasoline is extremely flammable and highly explosive, which could result in death or serious injury. (00028a)
Use care when refueling. Pressurized air in fuel tank can force gasoline to escape through filler tube. Gasoline is extremely flammable and highly explosive, which could result in death or serious injury. (00029a)
Modern service station pumps dispense a high flow of gasoline into a motorcycle fuel tank making air entrapment and pressurization a possibility.
Octane Ratings
SPECIFICATION RATING
Pump Octane (R+M)/2
91 (95 RON)
Trending Topics
Outstanding HDF Member
Joined: Dec 2008
Posts: 2,007
Likes: 353
From: Ohio
As long as automotive fuel is stored properly in an enclosed container like an airtight fuel tank, it will maintain its usability indefinitely regardless of the ethanol content. Evaporation and exposure to air is what causes fuel to degrade. Not how long it is stored. Unlike carbureted engines, most EFI systems are sealed from exposure to air.
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Extreme HDF Member
Joined: Jun 2011
Posts: 14,731
Likes: 2,535
From: Mountain Top, Alabama
To the OP: Go with the premium, octane trumps the other choices.
FWIW - I started adding Seafoam, 1 oz. to the gallon, to the King's fuel when the rides get cold and not as frequent. I also use it in all my small engines that may not get started often.
Couple of years ago, I bought a 4 stroke weed eater. The dealer told me ethanol fuel does cause problems in them over the winter, and the need to put Seafoam in it if it sits for very long.
Pressure washer gets it too.
Honda has a fuel advisory on ethanol I read once, search the web, it's out there...
FWIW - I started adding Seafoam, 1 oz. to the gallon, to the King's fuel when the rides get cold and not as frequent. I also use it in all my small engines that may not get started often.
Couple of years ago, I bought a 4 stroke weed eater. The dealer told me ethanol fuel does cause problems in them over the winter, and the need to put Seafoam in it if it sits for very long.
Pressure washer gets it too.
Honda has a fuel advisory on ethanol I read once, search the web, it's out there...
Cruiser
Joined: Oct 2012
Posts: 124
Likes: 3
From: Rome, GA
Fuel Stabilizer
FWIW, I have been using Marvel Mystery Oil as a fuel stabilizer for over 35 years. No problems with fuel or components. I keep a bottle in the right saddle bag of my '02 RK and pour in one ounce or so every fillup. Quick and easy, cost effective way to keep the fuel system clean. The stuff has been around since 1923 and has a credible history. Smells nice too !
I run the 100% gasoline as often as possible.
I run the 100% gasoline as often as possible.