just referring to Harley's Screaming Eagle instructions on ECM Recalibration Required for their performance parts..you could swap the SE stuff with K&N, S&S, pipes and AC, etc..point is once you add performance parts they want you to recalibrate the ECM,,it's pretty straightforward..I don't really care what folks do..just these questions come up a lot asking for opinions on what to do, what is safe, what voids warranties, etc..playing it safe is, well, the safe bet

 

I dont think mufflers and an air filter constitute performance parts. And I believe some of the mythology is being perpetuated by the companies who are trying (quite effectively) to sell you things.

 

They are performance parts in any manufactures book when they increase flow in the system. The fact that they improve performance has been proven on the dyno many times.

The Harley Delphi ECM designed for motorcycles will only change by minute amounts detected by the narrow band sensors governed by software tables. It is limited by those tables as to how far it will adjust. You open up the air flow and you need more fuel to keep the balance in the system to allow the ECM to adjust within it's full range. Many auto's use wide band sensors and are able to adapt better than the narrow bands used by Harley.

As MJ points out do what you want with your bike....

 

well they are according to HD..it's all out there on their website, the parts instructions, etc. and a lot of people tend to formulate their own opinions and interpret things differently..for me it's always been plainly written and documented comprehensively enough to follow..I defer to the manufacturer over internet opinions..but that's just me..sure there's been plenty of folks who forego the proprietary instructions and believe in the 'conspiracy theory' you mention..I've always had good luck and been very satisfied with the results of following instructions..others results may very

 

Well, a lot of valuable input. But looks like I won't be doing any upgrades any time soon as today my bike started making an unusal noise. Similar sound to a diesel engine turbo on a Mack truck. Have to take the bike to the dealer to figure what's wrong. Today I am a sad, sad owner

 

Sorry for your troubles,hope it is not serious but I agree with all the guys recommending a retune.
Any way I am outta here as you are talking K&N replacement filter and I came floating in with the screamin eagle filter upgrade which is another animal! Done my mandatory retune already , cheers

 

Exactly why I took the new wrap coverage. Otoh, that truly sucks for you.

 

So..... question, Vance and Hines fp3 or a power vision tuner? Which one is better?

 

Depends on what you plan on doing down the road. I prefer the vision and so do the tuners in my area. If your not going more than stage 1 with a download and auto tune i doubt it matters much.

 

I have had great luck with power vision.. Heard bad things on fp3, not sure