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You get better gas mileage at altitude because of the decreased drag on the motorcycle with the thinner air. I get better gas mileage at 75 in the Colorado mountains than I do at 55 in Kansas. I told my wife that we needed to move to Colorado to save money on gas for the bike but she saw right through that. She said the 30% better gas mileage won't make up for the 200% increase in miles ridden. I just can't get anything past her! :)

In Kansas, once you have seen one hay field then the next thing you look for is a tree! When I'm feeling really adventurous, I look for a corner to go around. :)
I would definitely move...Guess even with such a short season I have it pretty good with roads, terrain and scenery.
 

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I'm going to quote this because I could not have said it any better.
"Octane does not offer any better fuel mileage, increase engine horsepower, or make the engine start quicker. Higher octane only reduces the likelihood of engine knock or ping. ... Because higher octane gas burns slower, it is more resistant to knock when subjected to higher RPM and cylinder pressures "
UNLESS you have high combustion chamber temperatures then a slower burning fuel is beneficial. Back in the 70's I was seeing 3/4 miles per gallon increase on the flat 4 fuel injected Porsche engine. I was a Diagnostician for VW at that time and had access to many examples. But again these engines ran around 300+ degrees of head temperature and were subject to early fuel evaporation...
So for a GW 87 should be just fine. IMO
 

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With the compression on the GW 1800 being relatively low is 93 Octane helpful or wasteful?
You're wasting your money buying premium when it's not needed for anti-knock.
 

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My Brother and I had the same 08 Goldwings and we ride together all the time. I'd fill with 93 and he 87 and the 87 would get 3 - 4 mpg better all the time. So Now I'm an 87 pumping Guy and now we get the same MPG.
 

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Back in the late 90's two of us did the four corner ride around the USA. Both of us were riding Honda PC800's (Pacific Coast). Only real difference was I was about 40 lbs heavier, I ran Metzeler ME800 tires and the other bike Dunlop's. We wanted to see if higher octane made any difference on gas mileage, so every 500 miles or so we would switch who would fill up using 87 or 93 octane gas. The results were consistent, who ever was using 87 octane got better gas mileage. After about 3/4 of the way around we both just used 87 octane.
 

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I was told by the owner of a Goldwing dealership, and I have read, the carbon build-up(also mentioned above) from the higher 93-octane can actually be harmful to a Goldwing engine, possibly bending valves. In this case, I trust the owner's manual and use 87-octane.
 

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Wow. Its amazing how the pendulum has swung from the: higher octane fuel is beneficial to the last few posts indicating a higher octane fuel is detrimental. There is no carbon build up from higher octane fuel unless for some reason your engine is not reaching operating temperature. Should there be any difference in mileage? A slower fuel burn rate does not equate to lesser BTU.
 

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Nor does higher octane/slower burn rate translate into more energy.
The only "benefit" to not using regular 87 octane gas (which all contains at least 10% ethanol where I live/ride) is that some stations here give the option of 91 w/o ethanol. The only time I'm putting it in the Wing is before it sits 5 or more months over winter. Even then a dose of StarTron additive for good measure to keep the fuel stabil and keep any residual water from separating out.
There will be no benefit to using higher than needed gas in a Wing.
The previous bike was a Honda ST1300. The recommended minimum octane for that was 91. It too, had fuel injection and knock sensors. It never made any detonation knock (even though the manual said it would be "normal" even with 91 in some situations) and delivered the best fuel mileage and longest mile range tank fills on 87.
I enter every tank fill in a log book and track the results. Have with all the bikes and vehicles. A bit OCB perhaps, I know, but all maintainence and tire changes also have a written record to look back on. It's been helpful several times.
 

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Nor does higher octane/slower burn rate translate into more energy.
The only "benefit" to not using regular 87 octane gas (which all contains at least 10% ethanol where I live/ride) is that some stations here give the option of 91 w/o ethanol. The only time I'm putting it in the Wing is before it sits 5 or more months over winter. Even then a dose of StarTron additive for good measure to keep the fuel stabil and keep any residual water from separating out.
There will be no benefit to using higher than needed gas in a Wing.
The previous bike was a Honda ST1300. The recommended minimum octane for that was 91. It too, had fuel injection and knock sensors. It never made any detonation knock (even though the manual said it would be "normal" even with 91 in some situations) and delivered the best fuel mileage and longest mile range tank fills on 87.
I enter every tank fill in a log book and track the results. Have with all the bikes and vehicles. A bit OCB perhaps, I know, but all maintainence and tire changes also have a written record to look back on. It's been helpful several times.
An ST1300 requires 91!? Uh oh, I have always put in 87 for 5 yrs and never had a problem.

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I have always thought that the better fuel mileage you get at altitude has far, far less to do with "speed", "octane" or "drag" than it has to do with the stoichiometric ratio of 14.7:1

Less air pressure = less fuel. Air pressure decreases at a "sliding rate" as altitude increases. Roughly speaking, you should have about 20% less air available in a naturally-aspirated engine at 6,000 feet than you would have at sea-level (for instance). Therefore, you would expect that you would correspondingly use about 20% less fuel...especially with a modern injected engine (versus carb'd). It follows that you would also have about 20% less relative "power" available as well.

With all the low-end torque that the GL can muster, most riders won't "crank-her-up" (or feel the need to at least) in response.

Check out the math for yourself. Look up air pressure tables versus altitude and see if your fuel mileage changes proportionally given all factors are equal ( like ambient barometric pressure. relative humidity etc).
 

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I have always thought that the better fuel mileage you get at altitude has far, far less to do with "speed", "octane" or "drag" than it has to do with the stoichiometric ratio of 14.7:1

Less air pressure = less fuel. Air pressure decreases at a "sliding rate" as altitude increases. Roughly speaking, you should have about 20% less air available in a naturally-aspirated engine at 6,000 feet than you would have at sea-level (for instance). Therefore, you would expect that you would correspondingly use about 20% less fuel...especially with a modern injected engine (versus carb'd). It follows that you would also have about 20% less relative "power" available as well.

With all the low-end torque that the GL can muster, most riders won't "crank-her-up" (or feel the need to at least) in response.

Check out the math for yourself. Look up air pressure tables versus altitude and see if your fuel mileage changes proportionally given all factors are equal ( like ambient barometric pressure. relative humidity etc).
The shop manual for my daughter's Rebel 250 states. "When riding above 5000' for extended periods the carburetor mixture will need to be adjusted."
Also in winter many wonder why their mpg goes down. It should go up right? Denser air in a given volume gives you more oxygen in the same volume. That's why turbos and chargers were made. People who say that are correct but the fluid (air) that you are moving through is also denser and takes more energy to push through... that and they change fuel mixtures for the winter months for gas and diesel.

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Not sure I fully follow the idea of "more energy to move" being a major factor, but the idea of colder, denser air requiring more fuel (due to the Stoich-ratio) makes good sense.
 

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Not sure I fully follow the idea of "more energy to move" being a major factor, but the idea of colder, denser air requiring more fuel (due to the Stoich-ratio) makes good sense.
Work = Force X Area. Area stays the same but due to greater density of the air "Force" must go up to maintain the same speed. Therefore more fuel per mile. The inverse is true which is what you explained by less atmosphere... same "Area" but less density therefore force goes down to maintain the same speed. Air resistance is not linear as you go up in speed. It is a cubed (3) function and really starts going up steeply once over 70 to 75 mph.

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… 91 w/o ethanol. The only time I'm putting it in the Wing is before it sits 5 or more months over winter. Even then a dose of StarTron additive for good measure to keep the fuel stabil and keep any residual water from separating out...
My one comment is that I use PON 87 however, I actually want an E10 in the tank when stored since the ethanol will help absorb any moisture so less likely to cause corrosion. What I do is add the stabilizer and fill the tank with PON 91 E10 before storage. The E10 will lose isome octane during storage but the 91 will keep the fuel within spec.

G.
 

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My one comment is that I use PON 87 however, I actually want an E10 in the tank when stored since the ethanol will help absorb any moisture so less likely to cause corrosion. What I do is add the stabilizer and fill the tank with PON 91 E10 before storage. The E10 will lose isome octane during storage but the 91 will keep the fuel within spec.

G.
One of the benefits of ethanol is that it absorbs water. To absorb some minor water in the fuel system is a good thing. A couple of the (many) issues with ethanol is that it absorbs water, even out of the air. It will absorb enough sometimes to the saturation point then it (the water) falls out of suspension and almost pure water drops to the bottom of the tank. This can leave you with equipment that won't start/run later.
Some additives/stabilizers will prevent this, to a point. So they claim.
 

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I enter every tank fill in a log book and track the results. Have with all the bikes and vehicles. A bit OCB perhaps, I know, but all maintenance and tire changes also have a written record to look back on. It's been helpful several times.
me too, I use the Android cellphone App called Fuelio
handles all the calculations for us.
Prior to that, I used a Spreadsheet, drawback to that was keeping receipts until I got home.

With Fuelio, I make the entries at the pump and it is done.
 
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