You need higher octane fuel generally in anything above 10:1 compression to prevent spark-knock. This is due to the higher pressures in the cylinder creating more heat, which can actually pre-ignite the gasoline. Higher octane gasoline contains the same amount of energy as normal gas but is actually more resistant to burning which allowsit todetonate at a more optimal time in the combustion cycle in high-performance engines. This allows the engine to use the energy contained in the fuel more efficiently, creating more power. Now, not only does putting lower octane fuel in cause a loss of power but it actually can ruin the engine in the long run, especially in motorcycles with compression ratios sometimes over 14:1.

 

i have a good friend of mine who puts midgrade in his tank because itis cheaper, his Fi light kept comin on . i told him to use premiumfor a while and see ifthetrouble codewould go away. it did and stayed off for the duration.cant say for sure the midgrade was the cause but just a coincidence, that it did go away and returned abit after he started using midgrade again

 

Hate to be the bad apple but... i put regular in my bike sence i bought it. no problems yet. runs like a scalded dog. I have seen the inside of my 22K mile engine and it was clean as a whistle. Valves, throttle boties, pistons, everything in great shape. and most gas stations here in the atlanta area only have regular due to gas shortages.

 

you can but why would you.

if you could bang the woman of your dreams or a plain jane...which do you think you would do?

 

I read somewhere that the US has some of the lowest octanestandard gasin the world. Also the octane rating is based on the minimum so you may get 90 octane marked as 87 at one station and exactly 87 at another. I live in Korea and we only have one type of gas, aside from LPG and diesel. Our octane rating I have heard is somewhere in the low 90's generally, and neither I nor any of my friends has had any problem with it, but since its our only choice we can't do anything about it anyway. I would definitely put super in if I had a choice though.