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Sorry if this is a dumb question, does anybody run race fuel? My friends who have YFZ's all use a 50% race, 50% 91 octane mixture. Any reason I couldnt do that with the fuel injection? Again I appologize for the lame question I just got my KFX yesterday :banana:
 

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Sorry if this is a dumb question, does anybody run race fuel? My friends who have YFZ's all use a 50% race, 50% 91 octane mixture. Any reason I couldnt do that with the fuel injection? Again I appologize for the lame question I just got my KFX yesterday :banana:[/b]
With stock compression you do not need or will show any benefit from using race gas mix. Premium fuel is fine.
 

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After having my car on the dyno so many time's and seeing the difference in gas from one station and even time a year, I do not trust CA 91 pisstane at all. Some gas stations 91 oct is no better then 87oct. Thats why I run a mix.
 

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After having my car on the dyno so many time's and seeing the difference in gas from one station and even time a year, I do not trust CA 91 pisstane at all. Some gas stations 91 oct is no better then 87oct. Thats why I run a mix.[/b]
I understand that but if you stay at a reputable gas station you should be good. In most of the U.S., regular gas has an octane rating of 87, midgrade gas is 89, and premium is 91 or 92. (Octane ratings are lower in the mountain west due to the effects of thin air on internal combustion.) Contrary to widespread belief, the octane rating doesn't indicate how much power the fuel delivers; all grades of gasoline contain roughly the same amount of heat energy. Rather, a higher octane rating means the fuel is less likely to cause your engine to knock or ping. Knock, also known as detonation, occurs when part of the fuel-air mixture in one or more of your car's cylinders ignites spontaneously due to compression, independent of the combustion initiated by the spark plug. (The ideal gas law tells us that a gas heats up when compressed.) Instead of a controlled burn, you get what amounts to an explosion--not a good thing for your engine. To avoid this, high-octane gas is formulated to burn slower than regular, making it less likely to ignite without benefit of spark.

The majority of engine are designed to run on regular gas, and Higher-performance engines often require midgrade or premium gas because their engines are designed for higher compression (higher compression = more power), and regular gas may cause knock.

Using high-octane gas in an engine designed for regular accomplishes little except more rapid combustion of your money. Some refuse to believe this, claiming, for example, that premium gives better mileage or more power. These people are in dreamland. Others say premium is purer or contains detergents that will cleanse your engine of uncouth deposits. Likewise misguided thinking--government regulations require detergents in all grades of gasoline. Some automotive types claim that using premium in a car designed for regular will make the engine dirtier--something about deposits on the back side of the intake valves. Also the slower-burning high-octane gas is more likely to produce less power when used in engines designed for lower octane fuels. Believe what you like; the point is, don't assume "premium" means "better."

Just trying to save people money.

-Bill
 

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Great post, I have long said that you should use the lowest your car/vehicle is rated for anything above that is just a waste of money. Also if I remember right MythBusters did something on this and concluded the same thing. This kind of information sharing is what makes these forums great.
 

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All very true but what actually comes out of the pump is hardly ever what it says it is. One month I had my car on the dyno using 76 91oct and had 0- counts of knock. Two months later nothing changed and air temps were actually lower and I got 6 counts of knock. I talked to my nieghbor and he said that gas companies commonly use additives in the winter to help prolong fuel durring storage and it is known to lower octane rating. Within a week of getting 6 counts of knock I put citgo 91oct in it and lost 14 hp due to the computer retarding timing because of knock. Two bottles of octane boost and all counts of knock were gone. Bad thing is that most octane boosters have so many addatives in them that they actually hurt things more then help them. I have owned dirt bikes before and with a mild mix they always tend to look far better inside upon tear down, then any of my friends stuff that only run 91 oct. I usually notice a couple degree difference in head temps as well. Paticularly in air cooled motors. I usually run about 25% race gas and usually vp(I think 104) and its about $40 for 5 gallons and that last a long time so the price isnt that big of an issue.
 

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Great post, I have long said that you should use the lowest your car/vehicle is rated for anything above that is just a waste of money. Also if I remember right MythBusters did something on this and concluded the same thing. This kind of information sharing is what makes these forums great.[/b]
Thanks, just trying to help.

I think this is going to be a great forum for info. :banana:
 

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Great post, I have long said that you should use the lowest your car/vehicle is rated for anything above that is just a waste of money. Also if I remember right MythBusters did something on this and concluded the same thing. This kind of information sharing is what makes these forums great.[/b]
And they ran a mercedes diesel on cooking oil!
 

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Quad runner is correct. Higher octane will not give more horsepower. It simply allow an increase in compression and advance spark timing which result in higher horsepower. The more air/ fuel taken in, the more power put out.
 

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I use klotz 112 and it runs great. It's not the horsepower gain in the fuel. It's the boiling point of the fuel witch doesn't evaporate at high temp. of operation. The other advantage is the good race fuel start faster and burns cleaner. I once burned a cup of race fuel and then a cup of 93, the race fuel burned clean with no smoke and 93 smoked like a coal plant. Witch would you rather put in your quad? If you do buy race fuel, buy good race fue not from a pump. Klotz sells fuel (3) 5 gallon cans for $100 at GNCC races
 

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If your at stock 12:1 compression there is no reason to run 112 octane.[/b]
I use 108 SORRY and this way I use it.

RACING GASOLINE
108 OCTANE
Klotz High Octane Racing Gasoline is designed for performance enthusiasts and racers
that demand the maximum level of performance. Special additives prevent gum
deposits and helps clean jets and injectors for reduced maintenance. Detergents
scavenge lead and carbon deposits from plugs and combustion chambers for troublefree
performance. A perfectly balanced distillation curve guarantees consistent burn
speeds and a stable flame front.
• Improves throttle response and acceleration
• Prevents pinging and detonation
• Eliminates gum and varnish build-up
• Prevents power robbing vapor lock
• Maximum burn speed and efficiency
APPLICATION:
2/4-stroke medium and high compression engines, up to
12:1 compression ratio.
CHARACTERISTICS: Typical ASTM Testing
Color: Purple
Specific Gravity @ 60°F: .7295 ASTM D 4052
Reid Vapor Pressure: 6.44 ASTM D 323
Research Octane: 110 ASTM D 2699
Motor Octane: 106 ASTM D 2700
Pump Octane (R+M/2): 108
Distillation F°: ISO 33405
Initial Boiling Point 100
10% 158
50% 214
90% 252
Oxygen M/%: 0 Elemental Analysis
Alcohols: None
Tetraethyl Lead: 3.8 grams/gal. ASTM D 3237
Anti-foam: Yes
 

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I have allways ran race fuel in my quad with stock motor, and have never had any issues. If anything I think it has help because race fuel is a high quality of fuel. Here is the Boiling Points for pump gas

93 Oc. pump gas

Initial Boiling Point 85
10% 126
50% 173
90% 201
Final 215
 
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