i have been using premimum gas in my 2003 silverado since i got it in june of this year..i just hit 9500 miles
but I think i saw a mention about using 87 octane
am i doing the bike harm...is performance suffering ?

seems to run excellent to me

rick

You're just spending money that you don't need to. These engines are low compression and really don't need to run the high octane fuel. Some people believe running premium can lead to SVS.

Paul

Yamaha states do NOT use high octane gas! 87 only. Premium gas will burn hotter and in rare cases cause problems. Save the extra $$$ for chrome.

Steven

I have a lot of trouble believing higher octane will burn hotter. Octane affects pre-ignition, it is not "more powerful". Short of gun carrying rights, I think octane is the most debated subject on bike/car forums! But I do agree its a waste of money, except I wonder about the cleaning capabilities of the additives they put in the high test (e.g. Shell) and maybe they are good for the FI bikes?

I get good results from 89 but you know 89 is like 87 by time it gets to the end of the hose right? Ha ha! 87 Is best, you will get more MPG from it. Running the more money stuff once in a while won't hurt though. I do right before an oil change when I do my Sea foam cleaning treatment. Have to go with what factory says on this one though, good 87 is fine. Where do we find good 87 though? What will E85 do Bad gas is so easy to get now a days, Keep that seafoam handy!

MS1700 wrote:
I get good results from 89 but you know 89 is like 87 by time it gets to the end of the hose right? Ha ha! 87 Is best, you will get more MPG from it. Running the more money stuff once in a while won't hurt though. I do right before an oil change when I do my Sea foam cleaning treatment. Have to go with what factory says on this one though, good 87 is fine. Where do we find good 87 though? What will E85 do Bad gas is so easy to get now a days, Keep that seafoam handy!

All that alcohol in E85 will dry out every piece of rubber even faster (and probably make the bike run like crap). Your parts supplier will love you for it, though...

I want good ol' leaded regular back. I'm showing my age...

RK

I have run Chevron 87 since day one and zero problems. I also drop in some Lucas fuel treatment every couple tanks just in case. And I always run up and over the rev limiter at least once every time I ride. No SVS. Just did 1,000 miles last weekend 70 plus and got 45mpg the whole way.

The only time you need to run high octane is if you have high compression pistons and a built motor, I run 91 she won't run on anything else

kurtfriedrich wrote:
I have a lot of trouble believing higher octane will burn hotter. Octane affects pre-ignition, it is not "more powerful". Short of gun carrying rights, I think octane is the most debated subject on bike/car forums! But I do agree its a waste of money, except I wonder about the cleaning capabilities of the additives they put in the high test (e.g. Shell) and maybe they are good for the FI bikes?


Too low an octane with too high compression leads to explosive detonation rather than burning. Detonation will destroy an engine in short order! Higher octane fuel burns slower than lower octane to reduce explosiveness.
I am an FAA licensed airframe and powerplant mechanic with an inspection authorization and I spent 45 years working on airplanes before turning to motorcycles. The day of the 9-11 incident the FAA grounded airplanes nationwide for a couple of months; no airplane work caused me to get into motorcycles. A customer once asked me what I thought about a modification for a Cessna 172 and a friend who was a retired airline captain said "that will definately inprove the performance." The customer said to the captain "what do you know about that modification?" The captain replied "absolutely nothing" and continued "I don't care whether you are flying a Piper J-3 Cub or a Boeing 747. The lighter an airplane is the better it performs. When you get dome paying for that mod your wallet is going to be a whole lot lighter; therefor you have to have better performance!"
When you use high octane fuel (expensive) in a low octane engine and you "think" it runs "smoother", "better"; you have wishful thinking to justify the expense.

Clifford

Thats well put Clifford and funny too. We used to snitch 115 octane av gasand run it in our cars in the AF. All it did was burn HOT. Some guys even used JP4 in their kerasine heaters, now you talk about REALLY HOT....