Fuel Octane, My 2 cents worth, or $4 worth

So this is not a question, rather just a statement. I would like to hear from others what there experiences have been. just for the sake of curiosity.
I have my first bike, a 1980 kz750 twin, and i have been riding it for over a month and have put on a couple thousand miles in that time. LOVIN IT!!!
I had been using the 93 octane fuel thinking that i was going to get better performance from the bike. then here lately i starting thinking that my carbs were getting out of sinc or needed to be cleaned. By chance, I was nearly empty so i just threw in a couple gallons from the tank for my lawnmower (87 octane) and the bike started running better. i ran that tank out and filled up again with 87 octane and the bike is running like a champ.
the bike is basically stock, the only think i can see that has been done is the airbox has been replaced with K&N filters. i am not sure if the carbs have had a jet kit installed or not... but my pocket book is very happy to know my bike runs better on the cheaper gas!
Happy riding!

what is the difference in running that you noticed.

The higher the octane the slower the burn, making it cooler and reducing detonation.

I guess the best way to describe it is the smoothness of the engine performance. with the lower octane i seem to have a more steady idle, whereas it was starting to "lag" some. also, even the acceleration and power seems to step up a couple notches. granted, these differences are somewhat slight, however, they are great enough for me to notice and choose to use the 87 instead of 93.

Most stock bikes from that era are designed to run on 87 gas. That's what I use on my '78 KZ1000.

On my '82 KZ1000, I run premium because it has higher compression Wiseco pistions in it.

Unless you've hopped up the engine, regular gas should be fine on a stock bike.

I'm no chemical engineer, but the way I understand it, octane level needs to be matched to engine compression.
Low octane fuel burns more easily in the cylinder, and will detonate BEFORE the spark during the compression cycle, IF the compression is high enough. That causes pre-ignition, or pinging.
Natch, this assumes that the engine is tuned and timed correctly.
KZ motors are low compression mills, and are made for regular unleaded fuel, 87 octane.
At current prices, I'm happy to fill up with Regual, and the bike runs fine. I have a 9-mile grade that I have to climb on the way home, and the KZ has always pulled it well, with no pings or knocks.

FWIW, my 76 900 runs like crap on anything other than 87.

It's a myth that many people believe that higher octane = more energy in the gas.

For ANY engine, here is how you buy gas: keep going down in octane until it pings or runs bad, and then go up in octane until it runs right. Buying higher octane than that is a waste of money.

same here. My 550 loves 87 and hates 93. I read somewhere once that using a higher octane than needed will actually lead to lower mpg. Using that argument, I think I finally convinced my girlfriend to stop putting the expensive stuff in our truck.

my 650 likes 87 a lot more then 91 or 93 octane fuel

Well i am really glad to hear that so many others have the same experience. i thought maybe it was just a coincidence at first or my imagination, but now that i think about it, even some older vehicles i have had ran better on the 87.

I run high test in my KZ1100s in the Texas summer. I run regular in them in the winter...You can broil a steak on the engine while sitting at a stop light here in the summer......chris3

A local shop here in Madison has a good writeup on Gasoline including a discussion about Octane.

www.motorcycleperf.com/techtips/gasoline.htm

It's an interesting read if nothing else.