What daredevils have updated air cleaner and mufflers without tuning? I have a 2019 FLHTP with the 114, and would like to change the air cleaner out for another stock air cleaner. Or a "Vance & Hines VO2 Black Naked High Flow Air Intake Cleaner Kit 17-23 M8 Touring". I am already running SE mufflers.

 

I have a theory, others who know more than I do may disagree. It is that you can do what you want to your machine and drive it afterwards. If the MEL doesn't come on, you haven't changed the air flow enough that the computer is no longer able to maintain the factory set exhaust parameters. If the factory tune is good enough for you, there would be no reason for a retune. If the light comes on, you will need a re-tune. If you just don't like the factory tune, eventually you will get it re-tuned whether you change the air filter and exhaust or not.

Now standing by to learn what is wrong with this theory. This applies only to computer controlled engines, a carbed engine can't readjust itself.

 

2023 114 with a Vance and Hines V02 and mufflers. No issues in 5,000 miles.

I am planning to put a true full exhaust this year and I'll tune it at that time. More mods to come this winter too that will require tuning.

 

I was not sure if the MEL on the Harley would produce a code for lean fuel mixture before damage occurs. I know my 2020 RAM diesel truck threw a air fuel code, I changed the air filter (after 30k miles) and the light went away.

 

2019 EG Std 107, full S&S Grand National exhaust system and a K&N air filter in the stock airbox.
No lights, runs better than stock, getting 48 mpg riding two up loaded for a trip.

 

Yes, the bike can adapt to changes. Especially when cruising in closed-loop mode where the exhaust sensor feedback is in play. When you twist the throttle the bike goes open-loop and will be estimating the correct volumetric efficiency (VE) to use for fuel calculations. If you tune the bike, the VE tables will be updated as required for your engine modifications.

Per AI search:
Harley-Davidson Engine Control Modules (ECMs) do not apply real-time fuel trims while operating in open-loop mode. However, they utilize adaptive learning mechanisms to indirectly influence open-loop operation based on data gathered during closed-loop operation.
Open-Loop vs. Closed-Loop Operation
• Open-loop occurs when the ECM operates without feedback from oxygen (O2) sensors, relying solely on pre-programmed fuel maps based on engine RPM, throttle position, and other variables. This mode is typically active during cold starts, hard acceleration, and high-load conditions.
• Closed-loop uses O2 sensor feedback to adjust the air-fuel ratio (AFR) dynamically to maintain a stoichiometric mixture (14.7:1 AFR for most Harley models).
Adaptive Fuel Values
Harley ECMs feature an adaptive learning system that stores corrections made during closed-loop operation into “Adaptive Fuel Value” cells, also referred to as Long-Term Fuel Trim (LTFT). These values are later applied to open-loop fuel maps. For example:
• If the ECM consistently detects a lean condition in closed-loop mode and compensates by enriching the mixture, it stores this adjustment. Over time, the stored correction profile influences the fuel delivery in open-loop mode.
Key Points
• Real-time fuel trims (like Short-Term Fuel Trim) are exclusive to closed-loop operation.
• Open-loop relies on static fuel maps but incorporates long-term corrections derived from adaptive learning during closed-loop operation.
• This system ensures smoother transitions between open and closed-loop modes and compensates for changes such as modifications to intake or exhaust systems.
In summary, Harley-Davidson ECMs do not actively apply fuel trims during open-loop operation but use adaptive learning to refine open-loop fuel delivery based on prior closed-loop adjustments.

 

This is something we started looking into right when the M8's came out and found they do not need a tune when upgrading air cleaners and or exhaust.

We have a great report written up on the topic with Dyno Charts & other Interesting Info.

Kevin and Dwayne have also done a video on the 17's-20's.
As well as the 2021-2023's.
This is not to say a tune would not be beneficial but simply that it certainly will not harm the bike to not have one with just these upgrades.

Ride Safe, Ride Free.

Shelly

 

I understand how the bike can adjust within certain limits. I was unsure if those limits included a different air filter and different mufflers. And with the combination of changing both of them,if it would exceed the parameters of adjustibility for the ECM.

Thanks for the info.

 

Thanks, I'll look atbthis videos!

 

I was raised, you made changes you had to re-jet.