Your expert riding buddy doesn’t know **** about octane, and engine requirements.

 

Run what the engine is setup for. Anything more is a waste and may reduce performance. More octane= less BTU's per gallon.

 

You wouldn't get more power with higher octane because there is no additional power in that fuel to be had. If your bike runs fine on the 93, then anything beyond that is a waste of money. If it pings on 93, something is amiss.

 

Those saying that there is less power with higher octane are correct. High octane is more resistant to combustion - which is why it's used in high compression and other engines likely to experience pre-detonation. Piston powered aircraft use 100 octane fuel (with lead) not for added performance but because it's easier on the engine. Most piston powered aircraft are designed to only make about one horsepower per two cubic inches of displacement and run modest compression ratios. Use what is recommended in your motorcycle.

Me? If the engine is fuel injected, has an ECM with a knock sensor that adjusts ignition timing, injector timing and the like ... then I run 87 octane; always have and never had a problem.

 

Years ago I used to run turbo blue
Once in awhile just to mess with a buddy of mine
That ran behind me, He never could figure out why
His eyes were burning when riding behind me.

 

Octane is another way to classify flash point. Compression creates heat, that is how a diesel works. About 22:1 compression ratio creates enough heat to ignite diesel fuel. Higher compression engines create more heat during compression. If the fuel octane is too low, the fuel will spontaneously ignite before the spark plug makes the spark. It ignites all at once and that makes the knocking, pinging we hear. Higher octane fuel has a higher flash point so the heat made during compression is not enough to make it light spontaneously, it "waits" for the spark. Octane is NOT an indicator of quality. If you are interested in the best fuel quality, consider going to "toptiergas.com" and read about the additive packages and see the list of top tier brands. Those who live in or near the Rockies will find their stations sell fuel that is a lower octane than the standard 87/89/91 available in the low country. The higher you go, the less dense the air is. When an engine sucks in less air, there is less heat created during compression so lower octane fuel works fine at higher altitudes. This is for normally aspirated engines. Add a turbo or super charger that can compensate for the altitude and the higher octane is needed even at higher altitudes.

 

I know the Motor Company says to use hi-test in my bike, I normally use Ethanol Free 90 Octane, but due to the gas shortage, I can only use 87.
I haven't experienced any issues at this point in time, but I am also shifting at a higher RPM , running a gear lower, and trying not to lug the engine.
Hopefully they will start selling hi-test this week.

 

@TriGeezerwe need to find the OP and see if 11 years later his engine held together the last time he logged in was 9/13/3013.... if it was pre-detonating it surely would have gone thru a set of connecting rod bearings and possibly pistons by now

 

No such thing as pre-detonation...

Low octane fuel can allow an engine to Detonate, which means the fuel ignites somewhere in the combustion chamber away from the spark plug.

Detonation occurs after the spark plug fires.

This is what we hear as a ping.

Preignition is when there is a hot spot somewhere in the combustion chamber, and the fuel ignites before the spark plug fires.

https://www.faasafety.gov/files/noti...reignition.pdf