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Discussion Starter · #1 ·
I was just thinking my cousin had a trx450r honda fourwheeler, and it required premium fuel. What octane level will you guys use in your cb/r500r/f/x? regular,mid, or premium? Sorry for the newbie Question...lol
 

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With a 10.6 : 1 compression ratio, it should run on regular.

Octane ratings tend to change with elevation. :D
 

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Ron ratings differ across the globe, I think oz & uk 98 is us 93 i think
 

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Could it hurt the bike to run say 89 or 87 octane instead or is that just for performance....just curious
If you have no other option I'm sure it would be ok being fuel injected I'm sure the ecu can compensate for lower octane, but if u have premium just run that, you generally get more mpg from better fuels so works out the same $$$$ wise as the cheaper fuels, but it's much better for the motor.
 

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Discussion Starter · #13 ·
If you have no other option I'm sure it would be ok being fuel injected I'm sure the ecu can compensate for lower octane, but if u have premium just run that, you generally get more mpg from better fuels so works out the same $$$$ wise as the cheaper fuels, but it's much better for the motor.
ok thanks I was just wondering...ill definately use 91 octane as it would still be less than 20 to fill up:D
 

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There seem to be a lot of questionable statements made here.

Higher octane helps to prevent preignition. If you aren't having preignition problems, the longer hydrocabon chains in the higher octane gasoline tend to ignite a tad late and actually reduce the engine's horsepower.

i.e., you pay more to get less.
 

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There seem to be a lot of questionable statements made here.

Higher octane helps to prevent preignition. If you aren't having preignition problems, the longer hydrocabon chains in the higher octane gasoline tend to ignite a tad late and actually reduce the engine's horsepower.

i.e., you pay more to get less.
Wouldn't most modern efi systems factor this in and adjust ignition timing to suit fuel???? Not too familiar with bike efi and how advanced they are compared to cars.
 

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Discussion Starter · #16 ·
Wouldn't most modern efi systems factor this in and adjust ignition timing to suit fuel???? Not too familiar with bike efi and how advanced they are compared to cars.
ok so now im confused i understand the delay in ignition from higher octane fuel but in general the 500r says 91 on the tank so isnt that what we should use??/
i would think that honda knows their engines better than any of us
 

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There seem to be a lot of questionable statements made here.

Higher octane helps to prevent preignition. If you aren't having preignition problems, the longer hydrocabon chains in the higher octane gasoline tend to ignite a tad late and actually reduce the engine's horsepower.

i.e., you pay more to get less.
until we see a dyno comparing 91 octane vs 87 octane we won't know. Other variables effect.

I've always filled 91 or up. You aren't saving much by going with 87. Another problem with 87 is that it generally comes with 5 or 10% ethanol. Ethanol is evil.
 

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Discussion Starter · #19 ·
until we see a dyno comparing 91 octane vs 87 octane we won't know. Other variables effect.

I've always filled 91 or up. You aren't saving much by going with 87. Another problem with 87 is that it generally comes with 5 or 10% ethanol. Ethanol is evil.
i agree ethanol basically evaporates your fuel and makes less mpg but in general ethanol helps keep your engine clean by burning the fuel more effectively
 

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ok so now im confused i understand the delay in ignition from higher octane fuel but in general the 500r says 91 on the tank so isnt that what we should use??/
i would think that honda knows their engines better than any of us
I'm not exactly sure on how your Ron ratings work in the US, just ru nit on what the sticker/manual/dealer recommends. Btw, lower octane fuels would cos the ecu to delay timing = less power.
Plus here in oz our higher premium fuels are cleaner and help keep the engine clean. If fill with 98ron compared 95ron I will save around $3 (55L tank) but get less km/per tank, so works out the same value wise but the 98 helps keep the motor clean. Unless it clearly states somewhere not to use 98 that's what I'll be using in my cbr.
 
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