Most everyone that I ride with uses 91.

I got stranded out in the middle of nowhere and had to use 89, and I noticed nothing bad at all, the bike ran exactly the same as 91 with the 89 in it. I have never ran 87 though.

I always use 91, unless I am stranded :thumbup

 

its only 3.5 gallons dont be cheap

 

i think the manual says 91 or higher octane only. Premium Gas Only as i recall from the yamaha r6 manual.

 

its not that im being cheap, i put only 91 in, i was just wondering if in fact the bikes ran fine with 87 in them.

 

I finally get to use this emoticon :rtfm

 

There's been quite afew posts in teh past and there's soem good info elsewhere on the net... but basically speaking, octane is just the fuel's resistance to detonation. Using a lower octane fuel will produce more power since it burns faster, so for the most power you should use the lowest octane fuel that does not cause your engine to knock.

Even though the 03 R6 requires at least 91 octane according to the manual and that little sticker that came on the tank, I normally use 87 or 89 and I don't have any problems.

 

87

 

87

 

There's been quite afew posts in teh past and there's soem good info elsewhere on the net... but basically speaking, octane is just the fuel's resistance to detonation. Using a lower octane fuel will produce more power since it burns faster, so for the most power you should use the lowest octane fuel that does not cause your engine to knock.

Even though the 03 R6 requires at least 91 octane according to the manual and that little sticker that came on the tank, I normally use 87 or 89 and I don't have any problems.

the part in bold is the part that hits the nail on the head. and t seems some people biks can get away with 87 while others need a higher octane. try a few gallons of lower octane to see whate she'll take. it does behoove you to use the lowest octane you can; for reasons of price and performance, but obviously you dont want to knock

 

the 99-02 manual says to use "Unleaded gasoline only". So if you are putting 91 in your 99-02 you are wasting money.

the 03+ says to use 91 octane or higher unleaded gasoline. so its your call if you want to listen to a bunch of lawyers about wht is best for your motorcycle.

 

I'm keeping my mouth shut this time around, I always get some dumb ass insisting that he is right and doesn't want to hear anything else.

So I am just going to post this:

:idea want to see someone put 87 in a '04 R6?

 

the 99-02 manual says to use "Unleaded gasoline only". So if you are putting 91 in your 99-02 you are wasting money.

the 03+ says to use 91 octane or higher unleaded gasoline. so its your call if you want to listen to a bunch of lawyers about wht is best for your motorcycle.

Damn, i didnt think anyone would get it right... 02 and older dont waste your money, 03 and newer use 91. SO SAYS THE MANUAL... Which may or may not be true. Unless you have certain mods done you will get nothing out of higher octane fuel. Most of the time... you can do timing tricks for a temp. hp boost. But thats a horse of another color.

 

I'm keeping my mouth shut this time around, I always get some dumb ass insisting that he is right and doesn't want to hear anything else.

So I am just going to post this:

:idea want to see someone put 87 in a '04 R6?

so the 99-02 through 03-04 have the same compression ratio's ? why would the manual recommend 93 octane in 03-04 , but not in the 99-02 ? unless im missing something? i have a 01 and use 87 ( not because im cheap ) i have heard the 93 is a heavier fuel and can lead to carbon build up , and the 87 is a lighter fuel making it burn faster thus causing better performance.

 

so the 99-02 through 03-04 have the same compression ratio's ?

And compression pressures.

 

And compression pressures.

damn i learn something new everyday - i always thought the 03-04 had a higher compression engine thus be the reason for the manual recommending the 91-93 octane.

 

If you go by PSI then yes it is slightly higher. But since when do the Japs use PSI as a measurement when designing engines.

 

i think the manual says 91 or higher octane only. Premium Gas Only as i recall from the yamaha r6 manual.

Read the manual! .. Im pretty sure the very smart eng. in Japan built em for a specific octane. I ran 91 pump gas in my pretty tight 03r6 this past weekend with some injector cleaner added as i ran VPU4 (92 octane) all season (no detergents).. Ran pretty darn strong!

 

Read the manual! .. Im pretty sure the very smart eng. in Japan built em for a specific octane.

So are you including their factor of safety that they put in there to insure reliability and to garantee the lawyers that there will be absolutely no possibility of pre-ignition knock or detonation??

I stand by what I said earlier, use the lowest octane fuel that doesn't cause knock. Anything higher will cause you a loss in performance (even though it may be very small) and be a waste of money.

Until this thread I didn't know that the 02 and older models had the same bore, stroke, and compression ratio. Just because those numbers are the same doesn't mean that something isn't different about the head that could cuase them to recomend a higher octane. Its more than just compression ratio, its the total engine design. Try running a 12:1 on a car and using 87 octane and you'll be having a lot of fun.

 

Also depends on the elevation. The higher the elevation the lower oct. needed. I will bet your bike will run like ass going throu the mountians in CO and such on 91+. Mine did. Was running at what seemed half power. filled it with 87 and it was good again. Not enough air up high to support 91+

 

the manual does say for 03+ to use premium fuel and I understand that hey have the same compreesion ratio but it could also have to do with the timing and amount of fuel that the efi models use vs the carbed models.

 

not to jack....

but has anyone run VPU4 on an 02? What kind of jetting issues did you encounter? What HP gains?

thanks

tim

 

From my expirance , mostlly with cars thou, but bikes are pretty much same thing, if you use lower octane gasoliine on the motor, it sometimes will run worse and thats because computer is trying to fix the octane isse by adjusting itself, retireing timing. So it's not like u really have to but yap it's better to use the kind of fuel factory recommend. I used anything form 87 to 94 and it dosne't relly make a big differance.

 

From my expirance , mostlly with cars thou, but bikes are pretty much same thing, if you use lower octane gasoliine on the motor, it sometimes will run worse and thats because computer is trying to fix the octane isse by adjusting itself, retireing timing. So it's not like u really have to but yap it's better to use the kind of fuel factory recommend. I used anything form 87 to 94 and it dosne't relly make a big differance.

motorcycles do not adjust their timing for fuel like cars do. That is why it is important to run the correct fuel.

vp u4 is good fuel...pretty cheap and makes good power and you will probably need to adjust the main at least 1 clip. I am no expert on carb tuning though.

 

Like i siad, i'm no expert on bikes====> yet lol

 

thanks for all the help guys. no more wasting money (or performance). ill try 87 and 89 and see how it runs