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what gas to burn

well,after reading up on detonation,and how quickly it can destroy an engine,I don't think I'll chance it.It just seems there is an ever increasing difference in price between reg.and premium.It used to be 20-40 cents difference,but as I look around currently I see almost a dollar per gallon difference.Around here the cheapest reg is about 2.47,I just paid 3.39 for premium.Thanks for the info,everyone.
 
jamesearl said:
well,after reading up on detonation,and how quickly it can destroy an engine,I don't think I'll chance it.It just seems there is an ever increasing difference in price between reg.and premium.It used to be 20-40 cents difference,but as I look around currently I see almost a dollar per gallon difference.Around here the cheapest reg is about 2.47,I just paid 3.39 for premium.Thanks for the info,everyone.
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jamesearl, my take on it is even if it cost me an extra 100 bucks a year to run the highest octane grade, it's certainly worth the peace of mind knowing I'm not going to burn a hole in a piston or worse. JMHO.:s
 
Back in the day before EFI, it was difficult to fine tune AFR and ignition timing as can be done with EFI. The simple solution to mitigate detonation was to run a higher octane fuel. However, with the advent of EFI and finer tuning, running premium fuel is often not necessary and, if running a higher octane fuel that required, emissions systems can actually be damaged. The exception to that is super or turbo charged motors; premium fuel is a must for those motors.

Many manufacturers, including the MoCo recommend premium fuel when those motors will run efficiently on a lower octane fuel. Many believe that if a little octane is good, more octane is better and that is just not always true. Running on premium fuel does not increase performance, make the motor run cooler or make your hair grow faster, etc.; it just costs you more money.:(

Google "what octane gas should I use" and read up on the subject; there are many articles on the subject and they all say the same thing; a link to one such article is included. Of course, what fuel one run is a personal choice; no issue with that; however, the choice should be an informed one.:s

What octane gas should I use?
 
Like I said in post#10, your ride you decide. I prefer and most importantly my scoot prefers no less than 91 octane. If I can't afford the few extra bucks a year for premium then maybe I should be riding a rice burner.:newsmile100:
 
If your bike does not ping or knock on 89 run it , as carbon builds up in your engine it may require higher octane as this changes your compression ratio but that is miles down the road
 
The higher the octane, the slower the speed of the burn; the lower the octane the faster the burn. If the burn is too fast, uncontrolled combustion can occur. This most often is heard as “pinging” and is commonly referred to as detonation. This is because instead of burning through top dead center of the combustion stroke, the entire charge is ignited too early and explodes in the chamber and acts as a bomb. Conversely, if the speed of the burn is too slow, it continues after the useful work can be done in the motor and manifests itself as poor throttle response, reduced power output and increased emissions and fuel consumption. An engineering fact: THE MOST HORSEPOWER IS MADE AT THE THRESHOLD OF DETONATION
 
Well,it seems like no one suggests 87(reg) octane,and the price difference between mid grade(89) and premium(93) is not great,the difference between 87 and 93 octane is almost a dollar a gallon.
 
Having a New 2015 bike, I'd be careful because it MAY have More compression...

The cams in some of the new touring bikes have the 255 cams Developing higher compression... You need to be careful there. ccc needs to be checked and if you are about 205...... No way will you run 87 octane... Like has been discussed, the flame front needs to Burn Not BLOW...

IF you understand the full principal of Burning, you MAY indeed try the 87 octane...

BUT you need to know how to listen for the tell-tail signs of Pre Ignition and Spark Knock...

HD has a Knock sensor that retards the spark When needed... I try to Never have it work on my bike... Shifting down and NOT LUGGING is very Important IF you plan to use Less Octane fuel...

I use 91 as it is Simpler... Even then in really Hot weather I Need to careful as I have a Lot of compression in my build... I probably run close to 220+ Down Low elevations and 200 at 4400 feet...

Compression = Power & HEAT

The tuning is very important when you are choosing Octane...

I use an SE off road tuner and EVERYTHING can be changed with it...:s

signed....BUBBIE
 
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