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How many of you have actual real world experience building motors?
Back in the day, I did a 460cc kit and cam on my '81 Hawk after I learned it was consuming oil. Tuning the carbs was the hardest part but at least it was a DIY job for just a few bucks. A tune on an EFI bike today would cost half of what I paid for the bike brand new.
 

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2020 Rebel 500 SE
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Yes, but that's actually on the low end of "higher compression". Which basically means you can run whatever octane you want.
That's why I wrote "NEED". Sure you can use whatever you want in your Rebel engine, as long as Honda says you can in the documentation ;)
I leave in France, at sea level, I do 600 miles a month with my 500 (10000 miles since I got her), I put SP95 E5 and E10 or SP98 (90 or 93 in US reference, we don't have 87 here) and I never noticed any changes in engine behaviour or MPG.
That's the only experience I can share with you :)
 

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2022 Honda Rebel 1100 ABS
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It says 87 (well 86), but mentions nothing about ethanol content. We are forced here to use 10% on everything no matter what grade the gas is. Because of this, is it still safe to use 87 or just bump it to 89?
 

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ethanol and octane are not related, octane is the rating method for the gasoline the alcohol is mixed in to- before it is mixed'
the alcohol can be thought of as a magic liquid that disappears without leaving a hint of it's when it burns non e will get you more bang for the, squirt that goes in , as alcohol is kinda bangless compared to gasoline. i get 5 to 7 more miles to the gallon with non e and my small engines run better. ethanol at higher concentrations than 15 % is corrosive to rubber and aluminum, only mildly but,,, remember what ethanol's purpose is? to supplement gas from alcohol, if it were viable as a fuel we would have increased the % a long time ago. ethanol has fewer btu's than gas per volume, btu's is what makes the engine go roundy
 

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Um, synnamdammit you need to do research on ethanol.
Such as Brazil runs on higher % ethanol, up to 100%. Yea, they have perfected engines that can use higher %.
Ethanol also is added to boost octane. Not in your local gas station, but in some circumstances it is.
 

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Um, synnamdammit you need to do research on ethanol.
Such as Brazil runs on higher % ethanol, up to 100%. Yea, they have perfected engines that can use higher %.
Ethanol also is added to boost octane. Not in your local gas station, but in some circumstances it is.
agreed ethanol is an octane booster, but octane and btu's produced when burning are not related, alcohol produces less punch per ,,, ah nevemind, you right i'm wrong the end
 

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No, I agree with you less bang with tank of ethanol.
E15 here is 88 octane, where normal E10 gas is 87.
But you have to fill up sooner using E15 IF you CAN use it and IF you choose to use it.
I choose to NOT use it.
 

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My '72 Trail 90 runs on 87 octane E0 so I get 93 octane E10 and leach out the ethanol using water. Ends up at about 87 octane. The alternative is traveling 100 miles out of my way to get 93 octane E0. Every other bike I own can handle E10. No E15 around here.
 

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2022 1100 DCT
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If you want to take care of your ride, and don't ride that often then just avoid ethonanol. And/or avoid mom m pop gas that is Hella old or super cheap like Walmart some circle K where they have water in their gas. I worked for city hall and one truck always ran like crap whe we got gas from local circle K.
 

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Ima little late to the convo but here’s my 2¢. I have been running 87 since new (2020) and today I added 1.5 gallons of 91 into my half full tank of 87 so a blend if you will of 89. The ride to my barbers after that down the 55 fwy in SoCal. My rebel 500 was way quicker and smoother on acceleration than it has ever been. Felt like I was going downhill. I’ve took this together to my barbers from work over a year now and even after that going back to work and home after was a whole new ride. Manual calls for repair gas and maybe 91 isn’t the answer but maybe in between at 89. That might just be it for me. I do gave have arrow heaters and a mussari gp muffler if that helps.
 

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Ayedrien, it's not the higher octane that's increasing power. The chemistry being used to raise the octane rating is also oxygenating the fuel. If the octane rating was increased using something like toluene which contains no oxygen, there would be no performance gain without raising cylinder compression or advancing the ignition. An actual octane molecule has no oxygen atoms. Ethanol and other oxygenaters can increase performance but they also have an affinity for water. I wouldn't worry too much if you go thru it fast enough. I think MTBE can only absorb half the amount of water that ethanol can.
 

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The HP difference could be related to the ethanol levels in the fuel. More ethanol less HP.
If it came from a station that sells E0 and mixed with what's already in the tank, it would yield an E5. I know Exxon uses a full 10% in their highest octane.

Another possibility or contributing factor could be a higher detergent content is used in the high octane which is something else Exxon does. It might run better on low octane after running a tank thru.
 
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