With the pipes and the airbox it is usually recomended that you rejet your carb.As far as fuel goes,dealers and the manuals will tell you 91.I've got the same set up on my 04 1200 xl and I had them re-jet it.Runs great but it sometimes will pop or tend to load up on colder days so I'll run a tank of 89 every now and then and I don't have any problems and I've put close to 8,500 miles on it since last December.

 

So, what do you normally run?

 

Mobile 91 is what I usually run in it.

 

I only run Premium 93 octane at mobil or 94 octane at sunoco....