Get a copy of the Fall 2006 Enthusiast Magazine published by Harley-Davidson. H-D states in an article in this magazine that the Dephi equipped closed loop ECM bikes to not need remapping with exhaust and air cleaner upgrades.

 

I am really wondering about this too, i have bassani prostreet pipes on my bikeand the stock a/c, some say i need a tuner with just the pipes and some say that i dont need a tuner until i get a new a/c, it would be nice to know for sure.

 

My '06 Dyna with V&H slipons did not need a tuner. It ran, and I think it obviously ran fine for the first owner, as he put 18k miles on it like that. I will agree that a tuner was not -needed-.

However since I put the TMax (and new air filter) in, the bike runs much, much better. It idles smoother, it sounds better, and it pops much less on decel. I also think (but have no proof) that it's running cooler.

 

I have a post that has a link to the a CAUTION where Harley says the EFI does not compensate for any changes to the bike. I don't know who, what, when, or where to believe.

 

The warning in your other thread refers to changing out the components of the 103 kit. The computer can not compensate for changes in displacement, cams, and compression ratio. That needs to be changed in the tune. As I stated in the other thread changes in these components is a big difference from the computer adapting to changes in the air filter and exhaust.

 

Before I installed my Tmax I was running the stock tuner but I had a set of Xieds on it just to keep it a little richer with the A/C and free flow mufflers.
I'm sure it ran cooler, before I installed them it would high idle when sitting in traffic, after I put them on it didn't do it once in a year of riding.