Pipes for street glide
Cruiser
Joined: Sep 2013
Posts: 142
Likes: 1
From: Illinois
Far from an expert here, but I am in disagreement with your comment that the only time a tuner is required is after an A/C unit is changed. Every mod is changing how the engine is breathing and therefore resulting in improper fuel/air ratio being delivered to the engine. There a so many forums discussing this topic over and over and most will share the same, modifications required some form of tune. It could be a simple Stage 1 download to a SEST/SERT or an aftermarket, but required.
IMHO
IMHO
Road Warrior
Joined: Oct 2013
Posts: 1,446
Likes: 5
From: Mesquite Tx
If the exhaust is restrictive and you replace it with a very free flowing system then the bike is going to move more air in and out. Thus needing to be tuned or risk running lean and doing damage. If the AC was flowing 100% max air with the stock exhaust on the bike and you replaced it with a free flowing system then the air flow would be the same and not need to be tuned. In theory this would not change anything. Personally the bikes already run lean from the factory so I could see the benefit of tuning a stock bike for comfort and probably a very small gain.
Stellar HDF Member
Joined: Feb 2013
Posts: 2,325
Likes: 333
From: Upper Providence Pa
If you are really in question of this, ask another forum. I too like to learn as I go. I have been working on cars and bikes a very long time and whenever you alter one, one must alter the other as well.. Intake/Fuel/Exhaust all go hand in hand.
And tdivy32, I want to bring this back on track to your original post...... it is a matter of what you like.. I hope this side bar has not taken you down a path that confuses the question
Last edited by GlidingJoe; Nov 18, 2013 at 07:31 PM.
Outstanding HDF Member
Joined: Jun 2011
Posts: 2,023
Likes: 6
From: New Jersey
Excerpt from Nightrider Technical notes:
Do I need to remap my ECM when installing exhaust and air cleaner upgrades to my 07 and later Harley?
NO, you do not have to do anything. You can put the mufflers/air cleaner upgrades and ride the bike without having to worry about the engine. The simple truth is that the ‘07 and later HD's will run just fine with exhaust/air cleaner upgrades and you do not have to do anything to the ECM at all. Closed loop EFI operation uses feedback from the O2 sensor to maintain a constant AFR,even if changes are made to the exhaust and air cleaner.
There is more independent proof that you do not need to remap the HD EFI when installing mufflers. The March 2009 (page 66) CycleWorld dyno-tested a set of slip-on mufflers on an '09 FLH, getting 5% more HP and 9% more torque on a "bone-stock, including EFI mapping" bike. Cycle World is not known as a big Harley cheerleader, so it would be a reasonable assumption that they are not going to do any special favors for MOCO. The CycleWorld information is right in line with what HD published in the Fall/2006 Enthusiast Magazine, showing a 3% HP increase and 7% torque increase, with slightly more restrictive mufflers and an air cleaner kit. American Iron Magazine has also published similar articles about "no remap" upgrades involving exhaust/air cleaner changes. How much information has to be presented to Harley riders that remapping of the ECM is not required for exhaust/air cleaner upgrades for closed loop bikes? When it can be shown that much of the"gain" in power, for bikes remapped with expensive tuning software and piggyback controllers, would have occurred without spending $400-$1000, riders need to start thinking about what they are really trying to accomplish on their bikes, rather than blindly following the "you must remap just to add exhaust/air cleaner" advice, that has been discredited. American Iron Magazine routinely presents exhaust/air cleaner upgrades on ’07 and later bikes, without doing any ECM remap's. As one of the premier HD magazines, you must assume that their technical staff has some knowledge about how the Delphi closed loop ECM works.
anyway, just sayin'...
Do I need to remap my ECM when installing exhaust and air cleaner upgrades to my 07 and later Harley?
NO, you do not have to do anything. You can put the mufflers/air cleaner upgrades and ride the bike without having to worry about the engine. The simple truth is that the ‘07 and later HD's will run just fine with exhaust/air cleaner upgrades and you do not have to do anything to the ECM at all. Closed loop EFI operation uses feedback from the O2 sensor to maintain a constant AFR,even if changes are made to the exhaust and air cleaner.
There is more independent proof that you do not need to remap the HD EFI when installing mufflers. The March 2009 (page 66) CycleWorld dyno-tested a set of slip-on mufflers on an '09 FLH, getting 5% more HP and 9% more torque on a "bone-stock, including EFI mapping" bike. Cycle World is not known as a big Harley cheerleader, so it would be a reasonable assumption that they are not going to do any special favors for MOCO. The CycleWorld information is right in line with what HD published in the Fall/2006 Enthusiast Magazine, showing a 3% HP increase and 7% torque increase, with slightly more restrictive mufflers and an air cleaner kit. American Iron Magazine has also published similar articles about "no remap" upgrades involving exhaust/air cleaner changes. How much information has to be presented to Harley riders that remapping of the ECM is not required for exhaust/air cleaner upgrades for closed loop bikes? When it can be shown that much of the"gain" in power, for bikes remapped with expensive tuning software and piggyback controllers, would have occurred without spending $400-$1000, riders need to start thinking about what they are really trying to accomplish on their bikes, rather than blindly following the "you must remap just to add exhaust/air cleaner" advice, that has been discredited. American Iron Magazine routinely presents exhaust/air cleaner upgrades on ’07 and later bikes, without doing any ECM remap's. As one of the premier HD magazines, you must assume that their technical staff has some knowledge about how the Delphi closed loop ECM works.
anyway, just sayin'...
Last edited by FenderGuy53; Nov 19, 2013 at 08:30 AM.
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Outstanding HDF Member
Joined: Jun 2011
Posts: 2,023
Likes: 6
From: New Jersey
Based upon the chart below, I think most folks would be quite happy landing anywhere in the 13-14:1 range.
Last edited by FenderGuy53; Nov 19, 2013 at 09:31 AM.