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I got a used 02 mean streak, it had dg hard Kromes power commander already installed and i was thinking what grade og gas to use. The friends i ride with all use premium and i was wondering do I need to use it or can i go down to 87 without lossing power or throttle responce?
 

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My ZX-9R says right on the tank not to use anything less than 90. Check your user manual, if you don't have one try to order it. If you can't do that well, I'm out of ideas. I would say a cruiser probably doesn't need as high of octaine to work right without screwing up the engine. Sport bikes have higher compression ratios than the cruisers.
 

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I'm quite certain that all late model Kawasaki cruisers require 90 octane or higher. The manual for my Vulcan says it requires 90 or better, so I'm guessing others do too.
 

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the manual does say higher than 90. I've read that other guys have used the lower octane without any noticeable problems. the way I feel about this is, I'm no expert on fuel products so I will trust the engineers that designed the bike. they know what works best for each application. I would rather take the word of a trained professional than the word of a guy that is to cheap to pay an extra 20 cents for a tank of gas.
 

· AZ's Official Mechanic
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use the lowest you can so that you have no ping/knock etc. from the motor. ive used the good gas and the low quality gas :roll: in my ZRX 1100 and actually noticed a power loss with the higher octane stuff.
 

· Official BTK Forum Pot Stirrer
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Typically, in my area, the octane selections are 87, 89 or 93. Now when on vacation this year in Montana and Wyoming, I noticed that they sell 85, 87, 89 and 91. No idea why the sell a lower octane, I thought it might be due to the higher altitude, maybe somebody could answer that for me.

I have read my owners manual, it says minimum 87 octane for my 1500 classic (antiknock index (RON+MON) /2 = 87) with a Research Octane Number (RON) of 91. I have not experienced any "knocking" or "pinging" while running 87 octane.

The two discussion threads below should be considered as well.

http://www.kawasakimotorcycle.org/forum/viewtopic.php?t=1406

http://www.kawasakimotorcycle.org/forum/viewtopic.php?t=51


just my .02 worth
 

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Ken said:
Won't lower octane gas foul the injectors though?
From my experiance with FI, lower octane fuel does not foul the injectors, Bad fuel does. Lower octane fuel just has a greater chance of knocking. I've always put the highest octane fuel in all my bikes. It was nice when gas prices were really high. I'd pay $2.50/gallon but it would only cost me $12.
 

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spok said:
Typically, in my area, the octane selections are 87, 89 or 93. Now when on vacation this year in Montana and Wyoming, I noticed that they sell 85, 87, 89 and 91. No idea why the sell a lower octane, I thought it might be due to the higher altitude, maybe somebody could answer that for me.
I'm no expert either, but I believe it has to do with the additives for pollution control. Metro Phoenix premium is 91 max, but further out it's 93. Must be the MTBE or ethanol or some such thing. That's one of the reasons the gas comapnies say gas gets expensive. There are a huge number of blends across the country depending on local pollution conditions.

As for octane. I agree with vaporgas2000.
 

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Hi lifter400,

Good question? Sorry if I'm alittle lengthy.

Use the recommended octane fuel from the manufacturer!

The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting

When bikes are put together at the dealership they are adjusting and tuning the bike to factory specs for their location at their altitude. As our bikes are driven at different altitudes the air/fuel mixture changes along with it. For the most part no air/fuel adjustments are needed. However, with major altitude changes adjustments should be made to the air/fuel mixture to maintain peak performance if your intention is to be at location for awhile.

If your bike was normally being driven around sea level the bike will experience a rich fuel mixture as altitude increases and visa-versa a lean condition if your bike comes from a high altitude(like from Denver to Los Angelos).

Being a Flight Instructor the octane question comes up alot. The air fuel mixture is always being adjusted for flight for different altitudes. Most general aviation planes use 100 octane low lead. Inside the cockpit we have a Fuel Mixture Adjustment Knob to maintain peak performance. We can't afford to have pinging or knocking while trying to take off. It would be nice if while we were riding we had a small fuel mixture adjustment knob on our handlebars.

Check out this web site its great:
http://auto.howstuffworks.com/question90.htm
What does octane mean?
 

· Road Snot Needs A Kleenex
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I used 87 when i first got the bike because i had a hard time finding the fine print in the manual that said "91 or higher". What I've noticed is the bike runs with no problem with 87 octane in cool weather (34-65 degrees F). Warmer or hot weather, when the engine runs hotter def need the higher octane because of detonation.

I run 91 min all the time since I found the "fine print" (2 monthe after I bought the bike), unless I"m in the Adirondack Mountains and can't get anything other than 87.
 
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