No. You do not need to run 93 octane.
93 octane
Banned
Joined: Sep 2009
Posts: 7,580
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From: The Internet (& Dyer, Indiana)
But I would certainly give it a thorough test before staying with regular.
The results will vary from one bike to another.
Stellar HDF Member
Joined: Apr 2010
Posts: 2,960
Likes: 1,988
From: CA
Exactly right. Higher octane gas is not "better gas", it is actually more resistant to ignition than regular gas. If your manual calls for 91, use it, otherwise don't waste your money.
Road Warrior
Joined: Sep 2009
Posts: 1,465
Likes: 62
From: Port St. Lucie, FL
My suggestion: When you need fuel try filling up only half way using regular gas. This way if you experience any knocking
down the road go to the nearest gas station and fill up all the way using premium gas to prevent any further knocking.
Now this suggestion is the quickest method in going to regular gas. One other method is to do the same in steps. Half fill using mid grade gas and see if there's any issues.
Stock big twins 96" engines compression ratio is 9.2 to 1 I believe. A Honda Gold Wing GL 1800 engine compression ratio is 9.7 to 1 and Honda recommends using at least 86 octane gas not premium.
Cruiser
Joined: Dec 2008
Posts: 126
Likes: 0
I run at least 93, do not want any pistons rattling down there. I do not cut expense when it comes to fuel, oil, oil filters and insurance. When I doing 70+ and want to pass, I want to know I have done everything I can to keep everybody happy down there. If something happens it is not because I cut a corner to save $
Nuff Said ...
Club Member
Joined: May 2007
Posts: 145,895
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From: 40 miles Northeast of Indy..
Thinking my manual say 91 or higher... hard to find 93, seems like most are 92 anymore.
have use 89 couple times when need gas and station don't have Hi-test. couldnt really tell any diff.
have use 89 couple times when need gas and station don't have Hi-test. couldnt really tell any diff.
Road Warrior
Joined: Apr 2007
Posts: 1,354
Likes: 1
From: S.W. Florida
I have been in areas where the best fuel I could get was **** fuel.
I had to do as you described. Baby the bike to avoid ping.
I am a firm believer that you should run the best fuel, so as not to have to "walk on eggshells" while riding your bike.
Besides that, one don't always hear engine damaging ping. It could be silent ping or hidden by other noise. No need for risk there unless you are a real cheapskate.
A few pennies per gallon is cheap insurance. Drink one less beer and you are money ahead.
BP 93 or Shell 93 is all my bike ever see's, unless I am on vacation and nothing else is available.
I had to do as you described. Baby the bike to avoid ping.
I am a firm believer that you should run the best fuel, so as not to have to "walk on eggshells" while riding your bike.
Besides that, one don't always hear engine damaging ping. It could be silent ping or hidden by other noise. No need for risk there unless you are a real cheapskate.
A few pennies per gallon is cheap insurance. Drink one less beer and you are money ahead.
BP 93 or Shell 93 is all my bike ever see's, unless I am on vacation and nothing else is available.
FWIW and JMHO, I also add StarTron to my fuel with every fill up. It helps burn the gas/10% alcohol mix and protects the system components like Stabil. I always keep 5 treated gallons in my garage and also use the StarTron in my generator here in Hurricane Alley. I always buy my fuel locally from the same station and use the same pump and get a receipt.
Do a little research on what 10% ethanol is doing to lawnmowers, weed eaters and outboard boat engine fuel systems. There are other options becoming available. Stabil has a new Marine formula as does Lucas.
Banned
Joined: Sep 2009
Posts: 7,580
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From: The Internet (& Dyer, Indiana)
The power in gas is it's BTU content and in the US all octanes have the same BTU's. So higher octane will have a little less power output because it burns less.
While higher octane is slower to ignite (which is what helps eliminate ping), it still explodes just as well as any other octane and is not 'less powerful'.
There are millions of dyno sheets out there to confirm that.
Based on your info, race cars should be looking for the lowest octane. But they don't.
Elite HDF Member
Joined: Dec 2008
Posts: 3,947
Likes: 1
From: Little Apple, Iowa, U.S.S.A.
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Seasoned HDF Member
Joined: Jan 2007
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From: anacoco, la
whether or not to use premium was not the question. the question was whether or not to use 93 octane. in a lot of areas, 93 is not even available. hd recommends running 91 octane. so even if you are wanting to follow hd recommendations, no, 93 is not required.
