About ready to do my first fill-up on the 06 Dyna SG.
The dealer said to use the 93 octane.
Is this what you all use, or can you use the 87 octane?

 

I use 91 because we don't have 93 here...

 

mine says 91, but all we have is 93 here

 

You'll get lots of opinions on this one and there are plenty of threads where this has been kicked around before. You can probably dig those up in a search if you want a longer answer. But do the math and you may find it is an easy decision. If you are going to do 5k miles per year, you'll save a whopping $30-35 (or even less) for the entire year if you go with the cheap stuff. That's assuming a $0.30 per gallon higher price and mid-40s MPG.

The higher octane fuels tolerate higher compression and/or higher temperatures before detonation becomes a problem. These engines in stock form are not high compression, but they do run hot being air cooled. I live in Florida where it gets mighty hot so the decision for me is an easy one.

I'd go with the manufacturer's recommendation here.
Kevin

 

93 octane... lower on my bike doesn't run as well and gas mileage is lower

 

93 Octane here

 

Never less than 91, always try to get 93.

 

If you try the lower (less than 91) octane, make sure you're carrying a small jar of octane booster in a tool bag or saddle bag. It's epecially true when you're in the "exploring" mode. Been in many small backwater towns with gas pumps selling 87 or 88 octane only. It can be a real real real long ride to the next fuel stop with your scoot sounding like a popcorn maker (It's part of my standard tool roll for travelling beyond the horizon).

It's not as bad if you find 89/90 octane fuel that is "enhanced" with ethanol as the alcohol actually has a higher octane rating than gasoline. The gas stations around here start selling that mixed stuff during the winter months for air quality reasons, and I've been able to run that in the cold months without any problem. Only saves "fitty-cent" a tank though. I've been told that the alcohol also helps keep the moisture (water) content down in the fuel during winter months - particularly if there are wide swings in temperature that causes a lot of condensation in your fuel tank (keep that baby full when not in use!)

 

91 here but i have used 87 but that was a total accident .. good thing i had a half tank of 91 in there so it was not too bad

 

ethanol loves rubber hoses and seals.... Not... If ran frequently.....