what octane do u guys run with brocks full systems and pc/air filter. I have always run 93 octane, but EJ@brocks said to run 89 for best performance/power with their brocks maps. Just curious if u guys run mid grade or premium with full systems, or if it will even make a difference
best octane with brocks/pc
- Thread starter hemi
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You will be safe as long as your motor is not pinging. I wouldn't gop below 89 for sure because yours is a 2nd gen. You might let your tank get almost empty and only put a gallon of it in and test it out. If the motor starts to ping fill it the rest of the way with a higher octane. I run 91 because that is what most of the gas stations around here that don't have ethanol in them.
Wayneovich
Registered
If the MAP is set up for 89 then you will be fine I have read through some fuel discussions on here that idealy you want to make the most power with the lowest rating of ethanol. Sounds crazy but these are from people who know their stuff.
GenII requires premium.
I really dont see how 89 would give more power or how it would "gain" more power other then 91+ octane. Here in MI is a normal of 93, which i run. I could be wrong, but hey im ready to pour some 110 octane
The higher the octane doesn't mean you will get more power. The lower octane you can run without the motor pinging will get you more power, because the engine will be running more efficiently. Higher octane fuel decreases the chance of detonation in high compression motors.
Seems weird that octane rating would effect power if you are only changing the fuel maps. My understanding is that higher octane has more potential heat energy but also will ignite at higher temp. So in higher compression engines it will not explode at the wrong time causing pinging/detonation.
Seems like to take advantage of that you would need to change either compression, timing, or valve duration right? I thought that's why racing engines and turbos run higher octane so their super high compression ratios can get more power without pre-ignition.
In any event, I would guess this is a minor difference in performance and running 93 octane is the safest bet.
Seems like to take advantage of that you would need to change either compression, timing, or valve duration right? I thought that's why racing engines and turbos run higher octane so their super high compression ratios can get more power without pre-ignition.
In any event, I would guess this is a minor difference in performance and running 93 octane is the safest bet.
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jefro
Registered
Brock has done alot of testing and for maximum performance 89 is the way to go, but, but even he says that if youre in a hot climate doing hard long pulls(2 up in the hills for example) you may have to run 91+ to prevent knock. And think about it, at the strip the motor is cool-not heat soaked, and you're operating at higher revs-not loading the motor before the torque peak like you do on the street. Around Michigan the mid grades don't get used very much and are the most likely to be stale so to be safe I run 93 but bump the timing up a couple degrees at the higher throttle openings above 6000 with Ecueditor to take advantage of the higher octane at wfo.
mestona
Registered
2 Wheel Tuner mag ran dyno tests using different octane fuels in the gen 2 Hayabusa. They found a much smoother power band with 91 octane vs 87/89. The Brocks info may be old (gen 1 bikes ran on 87 due to lower compression; 10.5:1 in the gen 1 vs 12.5:1 in the gen 2) and based on recommendations for the gen 1. No map/pipe/air filter in the world will lower your engine's compression so I wouldn't risk it to save a few bucks, use the highest octane pump gas available. 
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i'd be much more inclined to believe data from brock vs 2 wheeler tuner
Kaptain Kanji
Registered
Remember, all grades of gasoline from the same pump have exactly the same amount of energy in them. The only difference is the amount of Anti-knock chemical that's been put in each grade.
The amount of anti-knock or "Octane" chemical has an effect on the time at which the fuel will start to burn. This is why different Octanes will produce slightly different amounts of power from the same engine. To know which fuel works the best, you'd actually have to put the machine on a dyno and see what the bottom line is for each fuel grade. As smithabusa says, I'd probably go with what Brock says.
The amount of anti-knock or "Octane" chemical has an effect on the time at which the fuel will start to burn. This is why different Octanes will produce slightly different amounts of power from the same engine. To know which fuel works the best, you'd actually have to put the machine on a dyno and see what the bottom line is for each fuel grade. As smithabusa says, I'd probably go with what Brock says.
Draco1340
Registered
Not exactly. One of the cheapest "anti-knock" chemical used today is ethanol. Higher octane fuels regularly have the maximum amount of ethanol allowed by state law. BTUs/lb goes right in the crapper if your gas is 10% moonshine. I regularly measure alchohol at the track for other racers, and have consistently found lower levels with economy 87 octane pump gas, but there is enourmous variation from brand to brand, and season to season (yes gasoline changes dramatically in BTU content and molecular weight during the switchover from summer to winter blend nationwide.)
The Gen II motor is incredibly good at running on low octane fuel without detonation when properly tuned. Brock and others have found the most power made on a "stock" motor was with MR9; a special race fuel with only 87 octane. I've run 9.00s at 155 mph on Sunoco 87 pump gas with a proper tune, only because MR9 is banned in my state. I'm not telling anyone to run low octane in there motor. I'm just saying that running high octane is not the only option.
bobber
Registered
Mestona
I concur,,
Good post,,,except,,the gen I compression is 11;1 In my 04 manual . And it states,,That your motorcyle reguires regular gasoline with a " Minimum " pump rating of 87
octane . And to not run fuels with ethanol content greater than 10% and not to use fuels with more than 5% of methanol,in it,,,,,,I used to run some octane boost in mine and got a nice boost with it until I read the manual telling you that methanol with cause fuel system failures damage,[page 8
I concur,,
Good post,,,except,,the gen I compression is 11;1 In my 04 manual . And it states,,That your motorcyle reguires regular gasoline with a " Minimum " pump rating of 87octane . And to not run fuels with ethanol content greater than 10% and not to use fuels with more than 5% of methanol,in it,,,,,,I used to run some octane boost in mine and got a nice boost with it until I read the manual telling you that methanol with cause fuel system failures damage,[page 8
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jerryjaw18466
Registered
i mix cam2 100 oct unleaded
didn't mean to open up a huge conspiracy theory thread about fuels, oops. Just wanted to know what most of u guys run with a full system/pc. Ej@brocks said to run 89 for best performance with my brocks install, but i'll just stick with premium/high octane. So far she is running awesome after the full system install with no backfiring, stalling, hesitation, etc etc
Yep as others here have said 87pump works best with his pump gas maps. As long as a motor isnt pinging it will make its most power on the lowest octane. Lower octane fuel burns faster. So if you dont need the extra octane to fight off detonation it will just make for slower combustion. And less power equals poo
87pump gas and his pump gas track map moved my big ass to an 8.77 on the stock motor
87pump gas and his pump gas track map moved my big ass to an 8.77 on the stock motor
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