DK Custom Products

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FL-XiED Fuel Enrichment for Harley EFI Plug-n-Play..More Details

Availability: In stock
Item #: DK-FLXiED-10-NR
Manufacturer: DK Custom Products

Plug-n-Play Fuel Enrichment for Fuel Injected Harley-Davidsons FL-XiED Lowers Engine & Exhaust Temps - Improves Throttle Response Harley-Davidson DK Custom Nightrider Stage 1

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Dynamic Tuning For Harley-Davidson Motorcycles

Xtreme Inline Enrichment Device


A Cost Effective Alternative to an Aftermarket Tuner & Dyno Runs.

This Patented Device Dynamically Adjusts to Changes Made to Your Bike!

The Patented FL-XiEDs will Cool Your Bike Down & Make it Run Better!


The Patented Plug-n-Play FL-XiED-10 richens the Air Fuel Ratio from14.6:1 to 14.0:1 in closed loop mode.

Recommended for 1 of the 4 Set-Ups Below:


  • Stock Configuration
  • High flow air cleaner
  • High flow exhaust
  • "Stage I" (both high flow exhaust & air cleaner)

Will NOT Work with Stage II, Stage III, etc.  


Immediate Benefits:

  • Lower Engine Temperature
  • Lower Exhaust Temperature
  • Improved Throttle Response
  • Reduced Surging
  • Reduced Pinging



  • Touring  2010-2016
  • Softail  2012-2017
  • Dyna  2012-2017

 Recommended for: Stock Bikes, & Stage I Bikes (High Flow Intake & Exhaust) Will NOT Work with Stage II, III, or IV.

Note:  It is recommended that bikes that have full exhaust system upgrades, or those with the catalytic converter removed, use the FL-ViED-10 product.  Fine tuning of the O2 sensor signals may be required to optimize the fuel mixture when the catalytic converter is not in place.

Simple install-comes with instructions.  No tools required, installs in a few minutes.


They work inline with the smaller H-D Delphi heated narrow band 02 sensors and Delphi ECM to richen the fuel mixtures, adding 6% more fuel to the engine in closed loop mode.

There is an indirect richening of the open loop fuel mixtures through the learning mode, or adaptive fuel value action built into your ECM.  This ensures the richer 13.8-12.5:1 AFR's are ALSO adjusted in heavy/full throttle operation.

 LINK to All Dynamic Tuners

Kick ass product, bikes running cooler and smoother. -Lyle


"409” ignition wires provide continuous heat protection up to 600-degrees Fahrenheit

Posted by Stephen P Mullen on 10/1/2009 to HD Tech Notes


What do the 131/151 codes mean?
The codes are specifically listed as P0131 and P0151 codes. The description in the Service Manual is:
P0131    Front O2 sensor low or engine running lean
P0151    Rear O2 sensor low or engine running lean
The key point to look at here is "O2 sensor low" when analyzing what is happening with the XIED's in place. The O2 sensor produces a 0.0 to 1.0 Volt output. Any voltage lower than a preset threshold in the ECM can trigger the 131/151 errors. Lower voltage equates to a leaner fuel mixture in the eyes of the ECM. The XIED's take a higher voltage from the O2 sensor and "shift" it to a lower voltage for the ECM to read. In some circumstances, the ECM will see this low voltage as "too low" and trigger the code despite the fact that the engine is running rich enough. The IED's take advantage of this voltage shift to richen the mixture.
So the engine can be running rich and the ECM might still trigger the "sensor low" signal.
There are also other reasons that the ECM will trigger the codes that we will try to cover below.

Will these codes hurt my bike?
No. These are historic codes and are not active. As long as these are the only engine codes you have and you do not have an active Check Engine light on, they can be safely ignored.

Do all bikes get these codes with IED's installed?
No. Many bikes never see these codes. You could also have the codes and never know it. Unless you check the historical codes on your bike, you might never see these.

Do completely stock bikes get these errors?
 Completely stock bikes get these 131/151 errors on a regular basis as evidence that Harley has included a note to "clear and ignore" these codes in their Service Manual.

Don't historical codes mean there is a problem?
No. Historical codes only mean the ECM saw something it did not expect. If the code is considered a potential problem or there is a risk of damage to the engine, the ECM will turn on the Check Engine light. No such situation exists with the 131/151 codes. The Harley Service Manual actually notes that these codes should be "cleared and ignored".

I have read that these codes cause the ECM to revert back to open loop mode. Is this true?
No. The ECM will only revert to open loop operation if there is an active error code. Active error codes will cause the Check Engine light to come on. As long as you have no CE light, your bike will run in closed loop for normal riding situations.

When I take the XiED's off my bike, the codes go away. Doesn't this prove the XiED's are creating the problem?
No. It can be easy to confuse the installation of the IED's as the cause of the error. This is a normal reaction and quite understandable for the average rider. In engineering circles there is something known as "root cause" analysis. The "trigger" mechanism is not always the cause of a problem. In this case, the "trigger" is the IED's. The IED's do make the ECM more prone to showing these codes, but there are a host of issues that cause the codes. Harley has documented many of these causes in their Service Manuals. A copy of the specific section of the Service Manual is listed below.

Are there other things that can cause the error codes?
Yes. We have information from an EPA testing laboratory that there are several other issues associated with these codes. These are engineering issues that are deeply embedded into the HD Delphi ECM. Our information also indicates that Harley is aware of these issues, but does not have plans to create any upgrades to eliminate know problems.

Can you get rid of the 131/151 codes?
 It is important that a rider ensure that they have eliminated the common reasons for triggering the codes with the IED's installed. The primary triggers are exhaust leaks and loose O2 sensors. Even the smallest exhaust leak can trigger the codes. We have found that many of the bikes that have codes will get rid of them when they carefully check their exhaust system.

Can I just run my bike with the codes and not worry?
As long as you do not get an active check engine light, you can run your bike with the IED's. For any active check engine light, you want to have that checked to find out what is setting off the CE light.

Customer Reviews

They keep my bike cooler even in 90 degree heat Review by The Motorman
I have a 2007 FLHTP I use as a rental for my Ride Like a Pro course here in Florida. Doing low speed maneuvers on that bike in the 90 degree Florida summers, heated the bike up very quickly. I installed the X-IED's and they made the bike run cooler, plus, the bike has better throttle response. The install took 5 minutes. They really are plug and play. (Posted on 10/4/2023)
It Works Review by Luke
What ever it does, it works. Helps my bike run better and cooler. Thanks again. 2016 Road Glide Ultra. (Posted on 8/25/2023)
Excellent product and a must buy if you want to keep your warranty. Review by PreacherMan
Seeing I still want to keep my warranty for a little longer, I decided to install the XIED’s.
Very easy to install and the bike ran better and somewhat cooler sitting in traffic.
These things work and these along with the 606/TTI, the bike feels great!
I sold my other bike and it was a 114, this 103 really woke up by these add-ons and no real tune yet.
Thanks again DK for a great product and answered questions. (Posted on 9/14/2022)
Great product Review by Wolfman
Easy installation on my road glide. Literally unplug o2 connectors and plug inline. That is it. Ground to battery terminal. First ride out I was startled by the quick response of the throttle. Was not expecting that. There seems to be no more backfire out the exhaust during deceleration. I can't tell if it is running cooler as I have added other things to the bike. I have only ridden around 200 miles and i like the new feel of the bike. Overall great product. (Posted on 8/18/2022)
Easy install instant results Review by Vthunder
This product came to me quickly, the install took only a few minutes. I had check engine light on before install from CAT removal and aftermarket mufflers. Was afraid of running too lean, this part took care of that and the check engine light stays off now most of the time. The light still comes on now sometime during acceleration during gear shifting. So far am pleased with results, have ridden about 1000 miles since install. (Posted on 6/14/2022)
Very nice product. Review by Happy Road King
If you only plan on stage1, i highly recommend. I could tell right away a difference. Bike runs cooler, has power in the low end rpm's. Doesn't get the deceleration pops anymore. Very easy to install. My 2012 Road King is running so much better. (Posted on 5/15/2022)
Great value Review by Ron
Works as stated, definitely makes a difference on my 2015 Freewheeler stage #1. (Posted on 4/22/2022)
A true plug and play setup Review by PSO
This mod was so easy! Just unplugged the O2 sensor and placed in the two FL-Xied. When I installed I had only had V&H slip ons and it ran great. A week later my V&H V02 air cleaner arrived and the Fl-Xied handled that change with no issues. So far I am very pleased with the way the bike is running. (Posted on 3/30/2022)
Excellent Review by Wieland
I install the Fl-Xied on my 2013 Roadglide Ultra in about 30 minutes. The performance regarding power and throttle were immediate. Been riding for several hundred miles and the power and overall response of the bike are like night and day. Wished I would have discovered this before. (Posted on 11/1/2021)
Work as described Review by 2010 FLHTCU
I added these to my 2010 FLHTCU with factory exhaust, have to say it seemed to cool it slightly, then I changed exhaust and air cleaner S&S Pro Tune and Super Teardrop with neighbor hater mufflers. The bike runs great and no tuner has been used. Fuel enrichment seems fair and useable. Bike sounds great and runs much cooler with that combination. I have a Jim's Force Flow as well and it hardly cycles on now, it used to run constantly after it switched on. Now it only runs when I'm at low speed for a while. (Posted on 9/24/2021)
Good remedy Review by Vicloc
Affordable. Arrived on time. Clear instructions. Easy to install; less than 30 minutes. Until a friend told me, I had no idea that my Road Glide ran lean from the factory & even leaner after I added an open-air filter and new slip-on pipes. I am happy that I found this product to resolve the issue and extend the life of my motorcycle engine. I recommend. (Posted on 9/22/2021)
Easy install Review by Freewheeler
Installed in less than 30 minutes, between rain and being out of town I have only put a couple hundred miles on the trike, it sure seems to run much better than before. Can’t wait to get back home to put some real miles on it. (Posted on 7/27/2021)
2015 Road King Review by Johnny Cakes
This is the 2nd unit I have purchased. (Other was for a Dyna). Immediate response from stock (example: engine heat reduction and increased throttle response). Currently changed to full exhaust and will add big sucker. Not looking for maximum engine performance (I'm tool old for that anyways). Very pleased with this product. Been using it for 3 years now. (Posted on 6/30/2021)
Easy to Install, Nice Upgrade Review by W9awx
Purchased the enrichment plug and play kit for my stock 2015 Softail Heritage Classic. Very simple install. Total time was about 30 minutes with a bunch of futzing around figuring out where to run the ground wires. Engine sounds smoother getting the little extra fuel it needs. No barking on deceleration now and acceleration is much smoother too. If you do not have plans to move into a stage two, three, or four at some point, this is a no-brainer. (Posted on 10/29/2020)

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