Regular or Premium gas?

fz6xlr8r

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Nope, it just cost more. These engines are built so they can operate in every region of the world, even in places where good quality gas can't be found. Unless you plan to raise the compression ratio of the engine 87 octane will work perfectly.:thumbup:
 
S

sportrider

this thread made me reread that section ( 3-9 ) of the owners manual.

Your Yamaha engine has been designed to use regular unleaded gasoline with a pump octane number[(R+M)/2] of 86 or higher or a research octane number of 91 or higher.

I haven't payed attention but the little math equation looks familiar I think I've seen that on the pumps. I've always ran premium, normally its only .20cents a gallon more, even if my tank was bone dry it would only be a buck more. anyways, if anything it makes me feel better running 91.

:Sport:
 
S

sportrider

Holy carp Danny! That is $1.02 higher per gallon than it is here. I don't envy you.
that pic is from a rip off station in Idyllwild, I normally pay around $3.14 per gallon for 91.
still I wish I was paying 2 something!!!:Sport:
 

craig007

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The higher octane in premium does nothing for the (short term) performance of your bike. If it is designed for 87, that's all you need. However, premium gasolines usually have better additive packages. This means that they have more detergents that should (in theory) keep your engine cleaner and prevent buildups. This is a long term effect so if you looked inside two engines after 50k or 80k miles, you should be able to tell the one that used premium.

Given all of this, what do I used in my FZ6..... I use regular
 

poorwboy

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More octane means more power.Not true the octane number is a measure of a fuels resistance to detonation, or knocking.
High performance, high compression engines are more likely to detonate, and so require higher octane fuels. However, the higher the octane, the slower it burns and you want the fuel fuel to burn fast. But a fuel that burns to fast will cause detonation, so you want to use the lowest octane number you can for your motor.
The best race fuels are leaded (so no catalytic converters please ), whereas all pump gas is now unleaded. Lead increases a fuels resistance to detonation, and raises the fuels octane. Formulated racing fuels, however, can have a lower octane rating, but still produce more power than pump gasoline.
However surprisingly, the vp fuel used by ama superbike teams has an approximate octane of 93.
 
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VEGASRIDER

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I just read the owner's manual for the R6, they have instructed to only use premium unleaded of 91 octane or higher. Our FZ6 manuals recommends to use regular unleaded fuel. If these two bikes have the same engine, why do the owner's manual differ in what type of fuel to put in?

your thoughts?
 

Botch

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...and the FZ brochures all mention that it uses a "detuned" R6 engine, a lower octane is probably what's best for it.
 

DefyInertia

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I just read the owner's manual for the R6, they have instructed to only use premium unleaded of 91 octane or higher. Our FZ6 manuals recommends to use regular unleaded fuel. If these two bikes have the same engine, why do the owner's manual differ in what type of fuel to put in?

your thoughts?

Same basic engine...not the same exact engine. Poorwboy said it pretty well.

READ: Octane rating - Wikipedia, the free encyclopedia

Last, why doubt the yamaha engineers?
________
HEAD SHOP
 
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trailblazer87

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Just thought I would throw in another tid bit. Fuel injected cars have a knock sensor on the motor to retard the timing if detonation is happening. The higher the octane rating the more you can advance the timing.

Do these bikes have knock sensors, if so, the timing could be retarding a bit on the lower octane fuel and decreasing the power the engine makes.
 

Ferris

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My opinion is 12.0:1 is pretty high compression, so I go with premium It's not like it cost all that much given the fil up cost and mpgs.
 
W

wrightme43

What octane number should you buy?
Modern fuel-injected engines have engine management systems that can adjust to burn almost anything. However, if the octane rating is too low, the engine management system will have to richen the mixture and retard the timing to prevent destructive knock, resulting in lowered gas mileage. As you increase the octane rating of the fuel, you will hit a point where the engine management system can run the engine at optimum levels. At this point you have best gas mileage and best power. If you continue to increase the octane rating of the fuel, the engine management system does nothing, so all you are doing now is burning more expensive fuel for the same result. So, buy the lowest octane number that you can and still get your best gas mileage.

In the winter, or when it's very humid, you can often lower the required octane number. In very dry heat, for example in Texas, New Mexico, Arizona, S.California, you will most likely need to raise the octane level a bit to get best gas mileage.

THE ABOVE IS A QUOTE FROM BELOW

All About Gasoline
 

dako81

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Im going to run premium anyways because I just am, thats what I want to do, I don't care what other people do and I don't want to convince them to do different than what they want to. Anyways, in my opinion, the manual says regular, ok, but if the r6 manual says premium, well then I am going to run premium because I don't really consider .2 less compression, a slightly different cam profile, and different fuel injection "detuned". Sure it has less horsepower and less compression, but premium is for high performance engines right? Well I think any engine that is 36.6 cubic inches/.6L and has around 90-100 ponies is high performance. The new Z06 corvette has a 427 ci engine/7L with 505 horsepower thats 1.182 hp per ci. The fz6 has about 2.67 hp per ci. Sure the vette has more torque per ci, but it also has twice as many cyliners. But anyways. I also argee that theoretically you will ge the best performance and mileage by running as low of an octane as your conditions allow. I just prefer to run premium. Thats all.
 
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