There has been some discussion of the possible benefits of using a lower octane gas than is recommended by Mother Kawasaki in our machines. Let us know which octane you're using, and if you've got any particular reasons for your choice. Experimental data is of interest, so please share your thoughts. -bg

I actually run 93 Octane, cause that's what is sold around here. I've never tried 89 in my bikes, but I don't think it would really hurt anything.

87 ~ A BTU is a BTU.

I believe Kawi recommends 90 or higher. I have seen pics of fuel system parts that were coated with varnish and the owner believed that was caused by 91 octane pump gas. That's why I use 89 most of the time. Higher octane gas is less likely to pre-detonate so that is my choice if I am going to be running hard or if the weather is hot. When I fill up on 91, I almost always add a little Seafoam to the tank to prevent varnish accumulation in my fuel system.

As far as performance, I haven't noticed any increase in power with higher octane gas. It actually burns less readily and that is why it protects against pre-detonation.

Knocks a lot w/out flies, BTW.

Low octane gas = more power
High octane gas = detonation protection

You can realize a small increase in performance on the lower octane fuel, that I will not dispute. I'm not going to risk it on a high performance machine like this where I run it hard all the time. Gas is cheap, engines are expensive.

Kruz

* Last updated by: Kruz on 9/4/2009 @ 9:30 AM *

i run 89, ran 87 before i had the thin head gasket.

i run 89, ran 87 before i had the thin head gasket.

...but only for about nine seconds!

Kruz

* Last updated by: Kruz on 9/4/2009 @ 9:51 AM *

I put 93 only, I've had to put 91 in it on a couple
of occasions when there was no 93 at the pump and I really
needed fuel.

For the little riding I do on the 14 any fuel will be fine IMHO.

My bike under fairing actually says 95 octane... no clue were to get that.

91 calorie brew only for me. No light beer in my garage.

95 ron is uk lower rating
B-A

91 all the time
Didn't think I should go against what the mother says and I read manuals

With 12/1 compression, why would anyone go with a lower octane than 93? I know the bike has a knock sensor and all and the head is aluminum but still. Most of my engine knowledge is of the automotive hotrod type from my younger days. It just doesn't equate to me that people are running 87.

93 only herein 14, 93 and 1 gal cam2 in the 9 (13/1)

I only run 91 myself, because I run my 14 hard at varying elevations, in temps from a little over 100 degree's on down. With a 12 to 1 comp ratio it deserves the extra protection of 91

Slightly off topic here...

I remember a really interesting article from a few years ago
when both Mitsubishi and Subaru had major beef with a couple
of car magazines that had the Evo vs. the STI.
The tests were done in California and the cars had slower 0-60 mph runs
and also dynoed really low for whp.
Both manufacturers claimed that they were specific about their requirements
of 93 octane gas and as we all know that's not sold in CA.

Will try to post a link if I find it.
BTW both cars dynoed stronger with 93 pump compared back to back with 91 pump.

both of those are turbo cars

I have a VP staion locally that sells street legal 100 octane unleaded at the pumps. Kinda nice for us turbo guys. The $7.50 or so a gallon aint quite so nice tho I bought 5 gallons to put in the 14 for its maiden turbo run...just to protect from any boost spikes. I was told by my kit maker I can run 91-93 octane at my boost levels as long as I use some common sense. I still think I may mix a gallon or so of the 100 in my tank when I'm close to the station When I'm not I'll carry some good octane booster in my back pack in case I take a ride out Deliverance way, and can't find nuthin' but 87 And I do have places like that out here

I ran 91 before and the varnish in the combustion chamber was like thick epoxy to remove. Never again. 87 burns completely.

89 at sea level.
91 for mountains,track days and touring.
22K miles and still runs.....,hard.

You guys are lucky to have all those choices. We here in Toronto Canada only have one Gas station that sells the high octane 94 and there are not that many stations. I use 94 when I can & 91 at all other times.

Battleaxe said,

95 ron is uk lower rating

Hey Dattaway-I've religiously used 91.I noticed when I removed the throttlebody,inside the "chambers"there was this thick,black crusty stuff stuck in there,not huge amounts-but enough to have to clean off on a couple of em.Is that what you're talking about?You say 87 will NOT produce this stuff?Yet perform fine if not better than 91?Thanks.I'm curious as well-I don't want to damage my engine using an incorrect octane-87 is completely safe?My sticker said 92 minimum.Will I actually feel any change going to 87?Better mileage maybe?I run my bike quite fast at least half of the time I go on any ride.Will this 87 be a problem with our compression setups?(12:1).How could I tell if 87 WAS damaging my engine?

* Last updated by: blue07 on 9/6/2009 @ 1:24 AM *

Mass I would bet those cars have knock sensors on them. The computer adjust's the timing to match the fuel detonation point. So, my guess they will produce more power with more advanced timing. So the higher the octane fuel means the computer can advance the timing more. Our bikes do not have this feature. Would sure be nice if they did.

Anyway, so you run the lowest octane fuel you can get away with, without detonation, for the most power.

Doesn't mater how many times you tell people this simple to verify fact. People have been trained by the gasoline companies, premium fuel means "better fuel" and "higher performance". Most of the time, IT DOES NOT!!!!