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I don't have a FZ-09 yet but I plan on getting one as soon as the weather gets a bit warmer. I went to our local stealership today and sat on and gawked over one and I am pretty certain I will be buying in the next couple months.

Anyway, my assumptions are that Yamaha recommends 91+ octane and that won't be an issue 90% of the time. My question though is if it would be alright to occasionally fill (no more than half a tank if much of an issue) up with 87 with 10% ethanol. I farm for a living and may occasionally fill half a tank or so out of our farm gasoline tank, then I could obviously fill the rest of the tank with 91 or the highest I find once I make it to a station.

Has anyone ran 87?

Thanks!
 

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I think Yamaha opts for the high side of octane requirement. Same thing with their WR250r.
On the other hand my Suzuki V-Strom 650 with approx same compression ratio and bigger bore requires
but 87 octane.I know that they're are other timing factors,head designs ect.But C.R.and bore size are the biggies.

Bottom line:FZ-09 will probably run just fine under 99% of conditions on 87 octane.
Yamaha engineers get nervous and call for 91.
But who wants to take a chance? Kinda hard to hear detonation on a naked bike.
 

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Filled mine up with 93. The light had blinked for a while. The costs was 10.41$ so why not? LoL
 

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Filled mine up with 93. The light had blinked for a while. The costs was 10.41$ so why not? LoL
Because the higher octane gasoline is more likely to make it run rougher at startup than it is to make it run better at any time. They raise the octane level by adding stuff to the gas to make it take more compression before it detonates without a spark. Many brands add detergents to their "premium" grade gasolines - but that's to keep their octane booster from leaving residue - and it's just something more that you are putting into your tank that isn't meant to propel you.
 

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Because the higher octane gasoline is more likely to make it run rougher at startup than it is to make it run better at any time. They raise the octane level by adding stuff to the gas to make it take more compression before it detonates without a spark. Many brands add detergents to their "premium" grade gasolines - but that's to keep their octane booster from leaving residue - and it's just something more that you are putting into your tank that isn't meant to propel you.
Hmm, I thought it took less spark to detonate? My turbo eclipse called for 93. Since it was force inducted it actually ran a lower compression.

I don't buy it for more horsepower. I buy it to burn cleaner and be more efficient.
 

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actually high octane is less flammable, its true, and a turbo or blower rams more pressure into the chamber causing the same effect, thats why they typically run a low compression on those engines .. the key is balancing ignition timing, compression, and getting the max power out of something ..im not sure on these new bikes but if it senses 'knocking' and automatically adjusts timing you can be sure youre neutering the bikes power by running cheap gas, especially pulling off low revs .. but yeah .. old timers trick ... you dont need a full tank of premium to do the trick you can hit it every other time at the pump ..
 

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I have over 1000 miles on the bike and I have never put 91 octane in. The first fill was the mix with 89, after that, all 87 octane with 10% ethanol - no choice on the ethanol around PHX.

No pinging yet, and I'm listening for it.

As far as I can tell the bike doesn't have a knock sensor, so when it warms up here I will be paying attention and if I here pinging, I will up the grade.
Got 76K on my 1100G without issues and 35K on the bonnie - that does ping by the way, but by being careful and upping the octane when it needs it (summer time) - also no problems.
I predict no issues with the FZ
 
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Finally got the bike to ping this week - not that I have been trying to do it, but I was in the wrong gear (5th) making a rolling turn thru a left green arrow (20-25 mph??) opened up the throttle with the engine at somewhere around 2K rpm and there it was. Rolled off the throttle to a more gentle accell and pinging disappeared at 3K rpm. Engine temp was 205F at the time, air temp around 95F, dry air.
Put mid grade in at the next fill up and will probably keep it at mid grade for the rest of the summer.

Just checked our state fuel quality site and 87 is currently running a little over 88 ; 89 is just a little over 89 (89.5); 91 is just a tad under 91 (90.8)
Inspection Search
 

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Octane rating is essentially a Knock Retard rating. The higher the octane the more you can get out of an engine before it starts to knock. Presumably Yamaha tuned the engine for at least 91, so I would avoid putting anything else in the tank. I have 93 here, and all I use for the bike is shell. If you have ever had a car where you monitored knock retard (KR) you can see why putting in the right octane for the tune is essential.

I once got bad gas (93) in my mazdaspeed 3 and I was doing some data logging (4th gear 2500-6000 rpms WOT) and got 5-6 KR. I finally figured it out that it was just the bad gas. So i don't buy gas from that station anymore. Octane is important.
 

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5th gear at 20 to 25 MPH????? Dude, downshift that thing! Even when I'm running 65 to 70 MPH, I'm rarely ever higher than 4th gear and the only reason that I would be in 5th or 6th is if I'm running way low on fuel and need to get a bit better mileage.
 

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Altitude will play a factor in this , the lower , the more knock. My wing calls for 87 but at sea level it knocks on 91 .aloso the wing gets better mileage at altitude , less air to push through
 

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I have always run 93. If not available I would use 91. Upstate where I go occasionally there is a Sunoco with racing fuel, I think it was 108, maybe 110. I put a gallon of that in once just to see, theres a difference, but 93 is good for me. :) besides 93 is recommended by Yamaha
 

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They don't even sell the good stuff here anymore. I haven't seen anything over 90 in Alaska in years. But nobody seems to sell ethanol either. I guess they just keep it simple, and expensive. Regular 87 octane was $3.79/gal yesterday.
 

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They don't even sell the good stuff here anymore. I haven't seen anything over 90 in Alaska in years. But nobody seems to sell ethanol either. I guess they just keep it simple, and expensive. Regular
87 octane was $3.79/gal yesterday.
87 is the same price here. Wow, no good gas in Alaska? That's wacked, I wonder why. Isn't that where a ton of oil comes from?
 

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In this area, the available octanes are 87, 89 and 93. I use 89 since there is a hell of a jump in price to go to 93. I tried 87 once and didn't see a problem. I also tried 93 and it seemed to run worse. I use the lowest octane I can find in my truck because that makes it start and run better. I believe that Yamaha recommends 91 just for CYA for those who ride at the limit.
 

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Regardless of price I won't run hi test because it sits in those tanks too long.
I run mid grade.2 points low but Yamaha is notorious for erring on caution when calling for 91 octane.
I blame the engineers.Same story with their WR 250R.
 
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