FZ6 slower with premium fuel?

[champion221elite]

After reading a fuel thread about a week ago, I decided to try running some Premium Unleaded fuel (92 octane) in my 2008 FZ6.

My bike is a 2008 model and is completely bone stock. No aftermarket air filters, exhaust systems, PC III and so on. I'm at 4700 miles and have been previously running Regular Unleaded fuel (87 Octane) since I bought the bike in August of 2008.

I ran the tank down to nearly the bottom and then topped off with almost 4 gallons of Shell brand 92 octane. After riding for several miles I got into some twisty stuff and noticed the acceleration felt "mushy". The engine was still running fine, however it seemed to lack the "snappy" feel in which I'm used to. Upon stopping at a rural 4 way intersection I noted there wasn't a soul to be seen, so I did a wide open throttle acceleration test. I banged through the gears as I normally would, but again, the acceleration felt a bit sluggish.

I know that a "butt dyno" assessment is a bit subjective, but has anybody else noticed slower than usual acceleration while running Premium fuel? I'm planning on burning this tank of fuel and then going back to 87 octane to see if there's any difference in the "seat of the pants" acceleration. I figured the FZ6 had significantly high enough compression, and a high enough red line to at least try premium fuel. Perhaps the Yamaha engineers truly did design the FZ6 to run perfectly fine on Regular unleaded fuel.

Any thoughts guys and gals?

 

[YamaSpeed]

Well that is interesting. I read a thread sometime last year about this and it made me change the way I thought about Octane ratings. That said I have still to run a tank of regular gas through my 07. I think I am going to try this.

By the way. What happened to your gas milage during this test?


thanks

Yamaspeed

 

[krushnuts]

I'm no mechanic, or engineer for that matter.

But, here goes the old 'a friend of mine' ... lol Anyways, he is one of the senior chemical engineers at BP. He rides a harley road king that has a top speed of about 150 kph when he uses standard unleaded, which is 91 ron here.

He reckons that the 98 ron fuel will burn cleaner (better for your engine) and more efficiently (better for your wallet) and provide more power (better for your ride).

His harley tops out at 160 kph with the higher octane fuels.

 

[champion221elite]

By the way. What happened to your gas milage during this test?


thanks

Yamaspeed

I can't give you a mileage number because I stopped keeping track of my mileage early this Spring. I use both of my trip-meters to keep track of my mileage for oil change intervals and the other trip-meter is used to keep track of my miles for chain lubrication purposes.

In all honesty, my fuel economy on Premium seems about the same. I was able to ride about 60 miles on the first two bars on my fuel gauge, so that seems about normal.

 

[VEGASRIDER]

Well the owners manual for the FZ6 states that it is to be runned on regular fuel, not premium. There is got to be a reason for that.

 

[champion221elite]

I'm no mechanic, or engineer for that matter.

But, here goes the old 'a friend of mine' ... lol Anyways, he is one of the senior chemical engineers at BP. He rides a harley road king that has a top speed of about 150 kph when he uses standard unleaded, which is 91 ron here.

He reckons that the 98 ron fuel will burn cleaner (better for your engine) and more efficiently (better for your wallet) and provide more power (better for your ride).

His harley tops out at 160 kph with the higher octane fuels.

That's an interesting observation krushnuts, and I'm certainly not going to knock it. I know some folks who run Premium in their Chevy Suburbans and claim an increase of 2-3 mpg. I tried Premium in my Tahoe, and I've seen no difference except for a higher cost at the pump.

I've chatted with a high performance outboard engine builder who also works at an Exxon plant in Texas. He claims that Octane is added to fuel to help control pre-ignition in engines. Regular unleaded (87 octane in the USA) has a higher BTU value per gallon when compared to Premium Unleaded (92 octane). Octane effectively raises the flash point of gasoline, and requires more heat and compression to ignite properly.

I guess it's a toss-up whether or not Premium has any benefits unless your engine is specifically designed to run on it. Hopefully others on this forum will have additional insight into the issue.

 

[YamaSpeed]

Well that is interesting. I read a thread sometime last year about this and it made me change the way I thought about Octane ratings.

Yup here it is.

http://www.600riders.com/forum/fz6-general-discussion/17794-what-octane-do-you-use.html

Give this a read. it may shed some light.

 

[xgrafcorex]

The exact wording from the 2007 owners manual is:

"Recommended fuel: UNLEADED GASOLINE ONLY"

"Use only unleaded gasoline. The use of leaded gasoline will cause severe damage to internal engine parts, such as the valves and piston rings, as well as to the exhaust system. 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. If knocking (or pinging) occurs, use a gasoline of a different brand or premium unleaded fuel. Use of unleaded fuel will extend spark plug life and reduce maintenance costs."

I run 93 octane and haven't had any problems. Then again, I can't compare how it feels to how it would be with regular (which I'm not sure what octane that is around here..80 something) because I've never done it.

That being said..my car is only 11.0:1 and requires premium gas. The FZ6 is 12.2:1..

 

[shamrocker]

This is how I understand it: "Premium" is somewhat of a misnomer, meant to make you think that it's better for your vehicle. In reality, it's only better for certain engines. Higher octane gas is made for engines with higher compression. Too low octane in a high compression engine and you get pinging (premature detonation). Putting too high an octane in a normal engine will also reduce the performance (delayed detonation?). Modern engines adjust the timing automatically to cope with the change, so it will still run "ok" but not as good as with the gas it was made for. So, unless you're experiencing issues, stick with the manufacturer recommendation :rockon:

 

[SeekGod1st]

My 2 cents is that you got a bad batch of gas. Either there was some water in it or something to that effect. Higher octane runs cleaner and adds performance to higher performance engines, look it up. Professional race vehicles always use higher octanes.

 

[Tailgate]

To all of you who believe paying for premium gas makes any difference in the FZ6---THANK YOU! ---Shell Oil Company, Standard Oil Company, Atlantic Richfield, Exxon Oil Company, etc. THANK YOU!

 

[buccs40oz]

To all of you who believe paying for premium gas makes any difference in the FZ6---THANK YOU! ---Shell Oil Company, Standard Oil Company, Atlantic Richfield, Exxon Oil Company, etc. THANK YOU!

yes they do for sure. they thank you all the way to the bank

 

[racerws]

I know several engine builders and engineering brainiacs, here's what they say:
(1) Regular, MidGrade and Premium are all Unleaded gas (no lead in any of them)
(2) Any given engine will perform it's best by using the LOWEST octane rating
that does not cause harm to the engine from preignition/detonation.
(3) I have personally observed that Premium seems to have a longer shelf life than the others, as I have Classic cars that sit around alot.
So, use Regular Unleaded for the best bang for your buck in the FZ6.

Just my 2cents

 

[trick6]

i'm no bike wrench, but i am an automotive technician and know a little bit about high revving performance type engines as well as the average internal combustion engine. i also know that the most common misconception about gasoline is that people think there's premium gas and then unleaded....it's all unleaded. it is illegal by federal law to sell gasoline with any lead in it. octane (most stations have 87, 89, and either 92 or 93) refers to the gasoline's ability to resist detonation, which is basically it's flashpoint. also, the higher the octane fuel, the higher the potential energy, or the amount of energy that can be released through burning. so, theoretically, a higher octane gas should produce better mileage and possibly more power. not always. every average car and race tuned cars that i've had the opportunity to try this on seemed to produce better throttle response on higher octane fuel. the reality is though, you can bet yamaha, honda, ford, chevrolet, and every other major manufacturer of road class transportation has a room full of guys sitting around figuring this stuff out for you, and the best thing you can do is run what the owners manual says to run. they've weighed the pros and cons of both as far as performance, wear and tear on the engine, and fuel mileage and figured out what the happy medium is. \

me, i've never fueled up with anything except 93 octane gas in my fz6, if only for the reason that it makes me feel better to spend the extra dough on my baby. i do feel confident though, that i would notice the slightest if any difference in that and 87 octane. i mean, these things vary on the chemical level that the average rider (i.e. someone who rides one bike, as opposed to someone like a mechanic who rides lots of different bikes on a daily basis and has some sort of comparison) will not realize.

for this particular thread, i agree with (sorry, don't remember the name) whoever said you got some bad gas. not that you got water in it because in an underground tank where gas is stored, if there was any water in it, it would sink to the bottom(water heavier than gasoline) where the pickup for the pump is, and you would pump mostly pure water into your tank and the bike wouldn't run at all. however, gasoline will go "stale". as you all know gas is highly volatile, meaning it evaporates quickly. the combustible elements(for lack of better term) will evaporate, over a long period of time, such as in the classic cars that sit around mentioned above, and the fuel will become less prone to burn as efficiently as it normally would.

with all of that coming from the layman's point of view, i will say that i personally know several fuel delivery truck drivers who have said that numerous times a gas station owner will slip a 50 or even 100 dollar bill into their shirt pocket to fill up the premium tanks with regular 87 octane fuel. so keep that in your paranoia banks too.

all of this rambling comes down to this: gasoline and the entire oil industry is a multi billion dollar industry all over the world, so you can bet it is very much a science when it comes to producing and selling it. but, there are so many variables between producer and consumer that there is no way possible to purchase and use gasoline scientifically to get the most possible bang for your buck. and it takes all of about 8 or 9 bucks to fill up with premium as opposed to 7.50 for regular? and neither one will do significant damage to your engine, even if used for its entire life, of that i am confident. so, really, who cares?? go with your preference.

 

[DaveOTZ]

I had a Merc Sable... My first new car... (ugly green, but thats not here nor there)
I was nervous and used 93 after 6 months they had to do a bunch of engine work...
So they tell me to use the 87... the explanation was something (like 13 years ago bear with me) to the effect that the 93 burned to hot and left too many carbon deposits... After using the 87 I saved a few bucks and had no more engine trouble... Was it the gas? Was it engine work that needed to be done? Who knows... I use 87 on Tin Fizzy... no worries My scoot needs 93 or idles too low...

Long story short... I follow the manual win/win

 

[Stumbles06]

I dunno if it's the same for you guys, but Shell Premium gas is a big No-No down here in OZ. It only ever causes trouble... especially in the higher compression engines.

There was another discussion on it somewhere here, but stuffed if I can find it right now...lol

:rockon:

 

[The Toecutter]

40 cents less a tank means nothing to me ..........I would pay $40.00 more a tank for 93 octane because I love my Fz6....and I would NEVER let it burn 87 octane fuel...

 

[xgrafcorex]

yes they do for sure. they thank you all the way to the bank

More like 7-11 to get a big gulp slurpee and spicy bite hot dog since I paid all of about 7 bucks to fill up my tank with premium today...at a BP station no less.

 

[Red Wazp]

40 cents less a tank means nothing to me ..........I would pay $40.00 more a tank for 93 octane because I love my Fz6....and I would NEVER let it burn 87 octane fuel...

Huh? Only use 87 octane in my FZ and FJR and both run great. I guess if you FEEL good so be it, but your machine is much better with regular gas.

 

[Andz]

We have two grades of unleaded here, 93 and 95. I have tried both and not noticed a difference in performance so I use the cheaper one.