I think you need to notify Kawasaki about the conflicting markings. I will also say different individual bikes will require different things. Nothing is perfect. Tolerance stacking in manufacturing could increase the compression enough to require higher octane in any bike. My KLX required 92 to keep from detonating when hot and under load. I knew from racing years before, that I needed to go higher octane. I will mention my 550 is totally tolerant of the 87 and that I have no owner's manual for either bike. Such was life.

With the bigger bore Vulcan piston it actually is tolerant of 89 octane. Many 650 riders run 89 and even 87. Why the stock 650 was that way I don't know. I do know the combustion chamber and piston top was clean when we rebuilt the top end due to ruined cam chains (2 tensioner failures in 15,000 miles) and burnt exhaust valves (my fault for late adjustment), when we did the big bore.

If your engine quit knocking and smoothed out with the half tank of 91 added, which actually will factor over the 89 because it's not a 50/50 split, you have pretty much experienced all the improvement you're going to get. If there is any additional it will only be because the ignition of the mix still wasn't quite right yet.

All octane does is increase the temperature point at which the gas will ignite. Once you eliminate any preignition, detonation, pinging, whatever you want to call it you will have the mix igniting at optimum. That's it. Any additional octane has no effect. You are right, that the correct ignition smoothed out the engine and increased the power, because everything is working right.

But it's good to talk about and know these things. Otherwise some riders might go chasing performance by boosting octane beyond where it is any help. And you may have helped some others deal with an issue of which they were unaware.

 

I absolutely agree with that. The only reason I still run 92 in the 678 is because I had very minor detonation when running the 89 on a hot day, so I am going the extra to avoid any detonation.

And reading about the Octane labeling differences could be a legit problem in that the manual for the KLXs might be a U.S. version or something and the panel sticker is for Canada. Weirder things have happened before.

By the way, give me a yell about the tensioner, what's going on so far.

 

I'll have to say I'm impressed with the number of people on this forum that understand the Octane rating system.

Too many people think Octane equals a Grade of fuel...like Grade C, Grade B, and Grade A. It's simply not so. Good quality 87 Octane rated fuel can be "better" than some of the 90+ Octane rated fuels, that are of lower quality. There are no more BTU's in a volume of 90+ than in the same volume of 87. There is no reason to run a fuel with a higher Octane Rating than is needed to avoid pre-mature detonation...UNLESS you have a turbo- or super-charged engine that essentially has a variable compression ratio...and THEN, the engine only requires higher Octane rated fuel when the boost is getting up high enough to make a difference. Well, there are perhaps some hotter-running, ECU-controlled engines that can eke out a tiny increase in power if it is constantly trying to maximally retard (or is it advance) ignition to take advantage of the higher Octane, but, that ain't a KLX system!

 

I've already sent an e-mail to Kawasaki worldwide...can you believe Kawasaki Canada doesn'T have an e-mail adress to send comments ?

 

Pretty interesting Myth busting from the "race gass" thread...

1. Myth: The higher the octane, the slower the burn.
Fact: In many cases, high octane gasoline has faster burning characteristics than low octane gasoline. It is rarely slower.

2. Myth: Too much octane reduces horsepower.
Fact: Trying a higher octane fuel and getting less performance is usually due to introducing additional variables with the different gasoline which can be overcome by re-tuning the engine.

3. Myth: Too much octane will burn up my engine.
Fact: The only time your engine is aware of octane is when it doesn't have enough. Using a higher octane than the engine needs does not hurt or help.

4. Myth: Street gasoline with oxygenates is junk.
Fact: Street gasolines of today, especially in California, are the best performance gasolines next to racing gasoline.

5. Myth: Leaded gasoline makes more horsepower than unleaded.
Fact: Leaded gasoline is legal for "sanctioned off-highway events only and does not allow the engine to make more power unless detonation is present. More power can be made with a street legal oxygenated unleaded gasoline than with leaded gasoline as long as there is no detonation.

6. Myth: Adding nitromethane to gasoline improves power.
Fact: Nitro knocks the octane number down severely, and makes the mixture way too lean. Jeff Smith, formerly of Hot Rod Magazine, tried this a few years back and destroyed an engine before he got the Air/Fuel ratio correct.

7. Myth: Octane number is power.
Fact: Octane number is resistance to detonation. Higher octane will increase power only if detonation is present.

8. Myth: The octane requirement of my engine is always the same.
Fact: Operating conditions like air temperature, barometric pressure, humidity, and coolant temperature have an impact on engine octane requirement.

9. Myth: Detonation and Pre-ignition are the same.
Fact: Detonation can hurt your engine; Pre-ignition will destroy it.
10. Myth: Mixing regular and premium gasolines is not a good idea.
Fact: All gasolines are miscible and no adverse effects will develop when mixing two or more grades. It is not really necessary to mix gasolines since there are three grades of unleaded gasoline at most service stations.

11. Myth: Octane number is simply a ploy by the oil companies to sell more expensive gasoline.
Fact: Approximately 70°/o of the cars on the road in the US are satisfied with 87 octane or lower. The other 30% need a higher octane gasoline. The higher octane gasolines are available for the people that have cars that need these products because of high compression ratio, or high performance in general. Many automobile manufacturers recommend the use of premium grade gasolines in some or all of their engines. (Cadillac, BMW, Corvette, Mercedes Benz, Lincoln, etc.) We make 76 Competition 100 Octane Unleaded Gasoline for people with highperformance cars that want a higher octane gasoline than what is normally available at the pump.

12. Myth: Gasoline is the same all year in all parts of the US.
Fact: Gasoline is "seasonally adjusted" based on the temperature that is anticipated in that particular marketing area. Changes are made at least six times per year in all areas of the US except Hawaii. A "seasonal adjustment" means that the gasoline is
blended to vaporize more readily in the winter than in the summer. This feature allows cold starts without stalls, and good driveability (no hesitations, stumbles, etc.) while the engine is warming up.

13. Myth: My owner's manual says to use premium grade gasoline, but I use 87 octane and don't hear any ping.
Fact: Many engines that have premium fuel recommendations also have knock sensors. The knock sensor knows when the engine pings and retards the spark timing until ping is gone. This all takes place at a sound level below what the human ear can detect, so the knock sensor may be saving your engine even though you don't know it. The retarded timing will reduce horsepower and fuel economy, so it is best to stay with the car manufacturer's recommendation for gasoline octane.

14. Myth: I buy premium grade gasoline because it has more and better additives to keep my injectors and valves clean.
Fact: All gasolines sold in the US are required by law to contain an additive that will keep injectors and valves clean. Tests are required and the additive must be licensed with EPA before it can be used. Most companies use the same amount of additive in all grades of their gasoline.

For your nearest 76 Racing Gasoline Distributor: 1-800-345-0076

Source: http://www.pontiacstreetperformance....mythsgas1.html

 

I think I'll save this post to show to others!

one question I have, though, is the ignition terms "advance" vs "retard". I was thinking that a delay in ignition is the same as a retarding of ignition timing....and that maximally delaying ignition is what a higher octane allows the ECU to do. Do I have the terminology reversed?

Thanks!

 

I'm lost. OP in the thread says that you made more power and the bike runs better on high octane, but then you continue to post links and quotes that seem to point to the contrary ?

WTF are you getting at ?

 

....perhaps that the OP's "seat-of-the-pants-dyno" may not be correctly calibrated....?

 

Didn't you read one of his responses where he said he's 'mechanically inclined?' I don't think any of us can hold a candle to that

 

Okay guys, calm down.
When I said "more power" I meant the engine has more power...not the gas. (I should also have written "more power than when I run it low on octane)
If the gas is "self detonating" at any point in the compression sequense, it is a fact you're not gonna get the maximum power output the engine is suppose to generate. So my point is you will never get more power than the engine was design for only adding octane, but you can get less power if you don't have enough octane. Pretty simple.
And of course the engine "runs better" because there is no self detonating, no pinking, no knocking or whatever you wanna call it !