2006 Deuce with SE pipes, air cleaner and the bike came with the SERT, so I'm assuming it's been remapped for that.

I didn't get an owners manual with it and internet searches have provided a lot of "I run 93 'cause it's the best" type comments, which I'm a believer in you should run what the manufacture tells you to, unless you mod it to need higher octance.

I run 93 in my car because of the ECU reflash, does the bike require anything similar to that? I know it's not FI, so I'm figuring probably not and whatever the manufacture states should be good enough.

 

My owners manual for my 04 Heritage states minimum 91. I run 93 because that is what premium is in Michigan...well most of it...

 

2003 owners manual says 91. I usually run ethanol free, which is Premium, 91 or 93.

 

My 2004 Softail owners manual suggests to use premium, so you should be using that. Lower octane gas actually has less energy than higher octane gas, but higher octane gas can be compressed more before ignition. Using low octane gas in an engine expecting high can result in some nasty results.

 

The book says 91 or higher. I always run 93 in my bike.

 

Stay clear of ethanol and buy premium. Here that is 91 octane.

 

I have had a few wrenches tell me no need for premium until you jack up the compression. That being said, I always ran premium except for a few times when it wasn't available, and it ran just fine on regular. Now my compression is 10.6 to 1, so I suppose that means I have to. The way prices are now, I think I would try regular in a stock motor and see what happens. If it doesn't ping and seems to run okay, I would use it.

 

Not sure where you guys are getting your fuel from, but here in Ohio, and everywhere else I have been, it has ethanol regardless of grade or brand. Might want to double check what you are buying. Around here the only pumps without ethanol are for boats, and advertised as such, and usually 89 octane for about $4 a gallon.

If you do live someplace that you can buy non-ethanol premium, I would hesitate to use it if you travel, only because if you are tuned for that, and then buy crappy ethanol gas on the road, you may have much bigger problems.

http://www.buyrealgas.com/

 

http://wiki.answers.com/Q/Does_shell...in_premium_gas

 

"If you do live someplace that you can buy non-ethanol premium, I would hesitate to use it if you travel, only because if you are tuned for that, and then buy crappy ethanol gas on the road, you may have much bigger problems."

This seems like flawed/backwards logic to me! Run crappier gas even if good gas is availabe because you might have to buy crappy gas when you are traveling???

Sorry, JMHO but I do not agree... run the gas that works best in your bike (usually premium) and stay away from the ethanol blends if you can!