We were at the HD dealer today, pick up some grips, and no I didn't trade today, I did ask them about decatting the header. Their response was I would need a tuner. Even just slip on mufflers would require a tuner. They said HD has the new bikes tuned very close and any change would cause it to run lean.

Now, I'm no tuner or super mechanic so I ask here. What's you opinion?
Truth or selling snake oil?

If I did have to have a tuner it wouldn't be the HD one, power vision maybe.

My whole idea of devatting was just to reduce heat for the wife...no muffler or air cleaner change, just decat

 

If you eliminate the cat and some new slipons added, I would say do a tune. Slipons only, no tune needed. As for me I'm on hold on eliminating the cat. Not sure yet how much more heat it will give out since it is a new design and larger than the previous versions. Guess I will find out soon since its starting to warm up pretty good here in Florida.

 

Yeah, I also looked at the new fan that mounts behind the rear jug....don't know for sure yet.
I'm comfortable but worry about wife

 

Casper, if it was me, I would install a set of VIEDS to richen up the AF mixture and forget about it. That's much cheaper than a tuner for what you have planned

 

My buddies 2017 with V&H slipons and no other mods is getting bad mpg numbers. I'll have to check with him but if I remember correctly he was hitting 30mpg or less. He was going to talk with his dealer to see what he should do.

 

You could consider a V&H FP3 Then no matter what you change you can dial it in from your cellphone. It really is a nice system. A lot of Harley shops are pushing them now. I bought mine from cycle solutions for $299.

I agree that no tuner required for mufflers. If you mess with the back pressure by removing the cat or change air flow. Then tune.

 

Before you decat, ride it in the heat with the s/o. The reason Harley moved the cat back to its new location was to get rid of the heat issue for the passenger.

 

This is exactly what happens when you open the exhaust too much. What size baffle does he have in the V&H slip-ons?
I am not sure what would be maximum on the M8's, but much past 1.75" for the stock (no cam)103's and you loose bottom end & MPG. The system needs some back pressure to keep from exhaust gas reversion.
So many think the louder pipes mean more power...WRONG !
LOL... Loud pipes make the right wrist work better also!

 

So true !

 

When I bought my 2017 Roadking. I asked about slip on mufflers and needing a tuner. Was told that if you modify the exhaust you need a tuner. two days later I asked the same question but a little differently. I asked if I put these Screaming eagle mufflers on did I need a tuner, was told no. I bought some Reinherts and there just fine.