Fuel types

I always put 91 in my bike. I guess because it seems to work fine and that's the most common fuel. What's the difference between that and 95 or 98? Will the CBX go better with higher octane fuel? Or worse?
I don't lack for power or squirt at the throttle, plenty enough for me!

Opinions?

The difference is in octane rating, 91 is the lowest you can buy in nz,followed by 96(95) and 98(97).The main difference is price.Some bikes are desgined to run on the "higher" octanes like the peformance sport bikes.If your bike is tuned to run on 91, stick with it, otherwise you are throwing your money away for little or no increase in performance

Na, she'll be fine on the regular stuff. Only difference you'll notice is in your wallet. Mind you weight saving there could be worth another 2kph. Pretty much any 80's bike will run fine on 91. Even ran Katana with 1186 big bore on it.

You could run an M20 on 91...but not a '69 bonnie with 11:1 pistons.

I run the Good Stuff in the Norton as it might still be 10:1....feels like it when it backfires...... I dubious of Gull as it might have ethanol in it.....not good for fibreglass tank.

Try using Gull's 97 octane - it has methanol in it and is great stuff.

I wish I'd used it in my turbo Falcon, alas too late now.

Diggers
What's the difference between that and 95 or 98?

Real bikes use 98 and are happiest on 100 if yer got it. But in the real world our petrol does not even come close to the proper petrol octane listed in owners manuals, it is just jazzed up with additives to 'make' those quoted numbers.

Lawnmowers, chainsaws and weedwhackers use 91

Diggers
What's the difference between that and 95 or 98?
Real bikes use 98 and are happiest on 100 if yer got it. But in the real world our petrol does not even come close to the proper petrol octane listed in owners manuals, it is just jazzed up with additives to 'make' those quoted numbers.

Lawnmowers, chainsaws and weedwhackers use 91

Geez Dodgy, you've put in a rather dubious group. My GS 850 at 10.5 -1 runs best on 91.

Real bikes only need such high octane gas to compensate for very high CRs and /or poor cylinder turbulence .

best for old bikes and cars

2/3 96
1/3 Race gas

The race gas still has lead in it so no need for additives

Octane, technically speaking, is the number of octane atoms in a molecule of gasoline. Gasoline ( we are leaving out the ethanol component's effect ) is a mixture of several hydrocarbons including heptane, benzine, and others. The number of octane atoms ( or its equivalent in the case of ethanol blends ) in the gasoline give it the number you see at the pump. It is a measure of gasoline's ease or resistance to burning when air and heat are present. High performance engines use high octane gasoline because they can compress the fuel more before igniting the mixture creating more power; if lower octane fuel is used, the knock sensors detect this and retard the timing to avoid engine damage which is why your mileage drops. Conversely, fuel mileage does not increase by burning a higher octane than needed; the higher octane's ability to resist ignition works against you and incomplete fuel combustion can result. The unburned fuel is dumped into the catalytic converters where it is burned, fouls the catalyst, and can cause failure of the converters.

Cmoore, you know stuff! I even sort of understand it.

Oh,so that's the problem with my R65 then,I've buggerd the Catalytic converter....

Thought your's had twin converters Motu!!

No I think that the problem is with your knock sensors. Better replace them ASAP.

The lawn mower runs better on 95. Much better starting as well. Good old Briggs and Stratton. The GSX 750 pinks like anything on 91. the CX doesn't really care but I have noticed better throttle response, if you could call it that, and smoother running on 95. Especially cold starting/running.