I'm totally confused. According to most on this board the stock ECM with 02 sensors is total junk, the bike is gonna melt down, and if you even change the air cleaner cover color it needs recalibrating and $900.00 worth of dino work. I like and read American Iron Magazine and for the past three months they have clearly and unequivocally stated that for mild mods like an air cleaner or exhaust change, the stock ECM with 02's can and will adjust to the new setup. For example, in the May, 2010, edition they installed an air cleaner and pipes on a Harley and noted, "However, we're not going to get the standard H-D ECM calibration that most dealers will want to install. We've found that most 02-equipped bikes do not need it since the stock ECM recalibrates itself to the new engine configuration in a few minutes via the 02 sensors. A check of the accompanying dyno chart tells the tale."

What's the real story? Is AIM just flat wrong? Aside from opinion, has anyone done any actual testing? If AIM is giving out bad tech advice, maybe I should read something else.

 

I would like to know as well...

I just switched to Rush slip-ons with 2in baffles, and have the Thunder true header kit coming...

I assume my 2008 FLHTP with O2 sensors will be able to adjust with this exhaust only setup change... is this correct?

Not really changing the air flow that much... if I added a high flow air breather, I would assume that might push the stock ECM setup parameters out of the range that it could adjust for on the fly, thus requiring a flash update...

I am not really looking to increase maximum performance, just wanted a better / louder exhaust tone.

 

The stock ECM is a quality piece,I don't think you can buy better,I have heard the same thing about mufflers and air cleaners,myself I think if I would change anything it just be mufflers without a TTS or a race tuner,the very least get the O2 checked.

 

Petti,
You've been listening to wrong choir. That ecm/ecu is an excellent piece of equipment. You better read some more. Also, the ecm/ecu will recallibrate itself for a stage one.

 

Rushbass, same basic situation. I have a 2009 FLHT and just ordered some Harley Fatshotz for it.

 

Well...I can attest to the ECM adjusting. I have a 2010 that was delivered with SE Air Cleaner, SE Nightstick slip-on, and the download. Yesterday, I put on a new (cat-less) 2-1 system. On the test ride (about 15 miles) I could hear moderate decel popping which faded some by the time I got home. Today, I rode the bike to work and noticed almost no decel pop at all. Since I did nothing from yesterday to today, I am going to chalk it up to the ECM making adjustments. I am no mechanic, but that's my experience.

 

You change any part and the first thing you will notice is the extra heat. I started with changing out the mufflers because i was told that i could with no other changes needed and DAMN! i started counting the seconds at every stop light because my pants were on fire. I quickly added the SE A/C and SERT. Shortly after i noticed a gold circle in the middle of the right pipe. Too late. I already burned the chrome on the right pipe. I pulled the baffle after only 4k miles and completely burned out the packing in the right pipe so now i had to change out the pipes because of that gold circle. If i had gone with the full mod instead of trying to do it a piece at a time i might have saved a little money.

 

As said above the stock ECM is absolutely a quality peice and has been used hundreds of times with a SERT/SEST to run 120-150 HP builds.

Can you do pipes and A/C with out a down load or tuner? Sure, for many miles, months or MAYBE even years,right up to the point where the piston melts off a ring land or a hole in the middle.

As someone who HAS dyno tested many different combinations, A/C only, pipes only, A/c and pipes together, A/C pipes and a download, A/C pipes and a SERT/SEST base map, A/C pipes ands a map I build, I can tell with out a doubt any change to a lean system makes it LEANER.

Up to 09 the narrow band sensors do not have enough range to adjust to the stock configuration so how could it possibly adjust to changes making it leaner?

As of yet there hasnt been enough time in our shop to test the HWB O2 sensors BUT, it still lean to start with so what make you think it going to adjust out when you install pipes and A/C making it LEANER?

Fuel Packs dont work, they typicly run around 16/17:1 till about 4000 rpms then go realy rich, based on the dyno testing we did.

O2 sensor eliminators are just plain stupid, kinda like telling Einstien to only use half his brain.

A real tuner like the SEST/TTS or dare I say a Power Commander that can be adjusted either with a dyno or Smart tune/V Tune/Auto tune is the way to go. Is it more expensive? YES! Is it necessary? YES! Its the cost of doing business, so to speak. Its a lot more expensive to buy the cheap crap boxes only to find out they aren't worth a crap and have to buy a real tuner later.

Will these bikes run for 100,000 miles if you do nothing to them? YEP! Been proven many times.

If you want to make changes a tuner IS a requirement

 

Theres always going to be a few that just don't get it. If you don't understand EFI systems let someone that does work on your bike.

 

Well, I went to the garage and did a quick preflight of the bike this morning. . . threw a leg over my bone stock Ultra, turned on the ignition switch, waited for the check-engine light to go out and hit the starter. . .this resulted in the engine cranking for about 1/2 second before it fired up and went to fast-idle for about 10 seconds, before settling down to about 1000 RPMs. I then proceeded to put about 100 miles on in the local area with my wife on the back. We drove fast, we drove slow, we climbed small mountains to slightly cooler air, we went in stop and go traffic in mid-seventies temps. . .the bike never missed a beat and couldn't have performed better in my opinion. Harley's fuel injection rocks!, as does the ECM that controls it, because I did what the designers intended--I rode it normally. . I wasn't trying to win a race with anyone, I wasn't trying to pull high dyno numbers or make a lot of noise.

When you start modifying the design of the engine and engine management, all bets are off as far as dependability because you introduce a lot of variables that the designers couldn't possibly foresee. The fact that the Harley fuel management can't handle engine mods doesn't make it junk. . . .