There is NO way an after market device supplier can test for all the "abnormal" modes and conditions that are both accounted for and TESTED by an OEM manufacturer! Just running their device and "not having a problem" is not the same as the several years of REAL development that goes into a production application. OEM development is done under extreme conditions that can be experienced by all the different USERS and environements in which the product will be used.

An aftermarket "SELLER" does not have the same regard or EXPOSURE to durablity issues as Harley Davidson as the maker!
Additionally, the "aftermarket" device maker does not possess the knowledge of how the ECM software REALLT functions.

How the software functions is critical to understanding what OTHER unintended consequences can be affect by the device!

 

First thought, what is this guy trying to sell?

Visit to web site confirms First thought.

Who the Hell is "NIGHTRIDER" ?

He's selling a "device" to change the "resistance" on the 02 sensor, that tricks the ECM, into changing the fuel/air ratio.

Might save a few bucks, but I can't see spending the best part of $20,000 on the worlds finest motorcycle. Then resorting to some "Jake Leg" patch to trick the computer. What happens when one of the resistors burns, or better still, frys your ECM. Then your gonna be "pissin and moanin" cause Harley's warrenty won't cover your bike

BETTER still, just jam a stick, into the ECM until you get the right reading, on the 02 sensors. Then glue the stick in the right position, and wrap it in "chrome" tape.

Just my $.02

Oh yeah havent had my coffee yet, does it show?

 

I did talk to the guy on the phone before I made a purchase and he did seem know quite a the ecm harley is using and gave me the impression he may be working with some who knows it even better than himself. I know a few people runnin them and seems they are having no ill effects from their use. If the O2 sensor signal is being changed on its way to the ecm to make the ecm believe it is running lean in return the ecm is richening the fuel I don't believe that if a resistor is being used that if it failed it would fry the ecm... just my opinion.. it might result in an O2 failure code, if that happened you would disconnect the inline harness that is being used and go back to the original configuration. I may just make another call and pose that question to this guy.

 

good stuff FBRR.....as always.
I just found this thread and was reading along shaking my head.
then you put it all back in line.

 

FBRR:

The IED doesn't fix the input to the ECM, it is a voltage divider that divides down the voltage output from the O2 sensor. The ECM is still getting real time feedback from the O2 sensor.

 

What everyone doesn't realize is the Harley ECM takes information and uses it to get operation data from Look up tables. A lot of Look up tables.

Info from Harley's SERT Tuning guide. i suggest you read the pdf.

Quote from SERT Tuning instructions
2006 EFI Dyna models come equipped with 2 “switching” sensors…also known as stoichiometric sensors. Unlike wide-band sensors which can measure and control over a wide AFR range (10-20), switching sensors can only control within a narrow range (+/- 0.5 AFR).

This offset control is accomplished with the ecm taking the data and adjusting using the information in the Closed-Loop Bias table. Closed-loop operation is only used when the engine is in a normal operating condition. There are several instances when the ECM goes into open-loop operation.

These include: warm-up, high load or high RPM operating conditions (such as WOT), when the vehicle is in Hot Engine Management, or any time the AFR requested is richer than 14.6.

By fooling the ecm it is using data that might be close but not really for what is going on. Or you kick the ECM, by throwing an error code, into Open loop mode. That's another table by the way.

For those that want to read how the ESPI (Electronic Sequential Port Fuel Injection System) works download this be patient large pdf.

 

Great thread, and very educational. This is what the forums are all about. Thanks to all the contributors, and keep it going.

 

Thanks guys for all the info. So basically the ecm can and will adjust but only in a very narrow range and the XIED feeds the ecm false information to make it think something else is happening. This can be good but might also give adverse effects.

It seems as if the best and safest way to change the AFR would be a product like the SERT or PC.

Very good info in this threaed

 

I will say this just one time and not waste my "meager"typing skills again.
The "NIGHTSTER" does not understand fuel control. The nature and way in which they choose to trick the system, does impact fuel control software.

I will try and not get too technical, but REAL fuel control used that 0-1 volt siganl as Milivolts! Shifting the signal results in real errors.

I'm sure some of you understand that when the signal is rich fuel is taken out, when the siganl is lean fuel is added in. HOW THAT HAPPENS is called fuel control. The actual mechanism of software driven fuel control, is this
( very simply stated and there is much more to control than what I am about to explain), The CLB or closed loop bias is really the switch point voltage. When the O2 sensor is above the line the system is rich, when the O2 sensor signal is below the line the signal is lean. What happens when the signal is LEAN!? Fisrt a proportional amount of fuel (pulse width) is added to the injector command. Then as time goes on ( again in MSEC) the fuel is increased in "incremental (INTEGRAL)" amounts ( smaller than a proportional but still an increasse in fuel), that happen until the O2 signal goes RICH. Then the same thing happens in reverse. Proportional decreases followed by ITEGRAL decreases. Those are the BASE units of fuel control. How much proportional and HOW much and how FAST the "Itegral" fuel changes are dependant on several things! They are different for speed and load as well as "HOW FAR FROM THE SWITCH POINT" the voltage goes, as well as the derivative value of the O2 signal. ( taking the derivative the the delta change in O2 sensor voltage indicates which DIRECTION the sensor signal is GOING. Rising or falling.

All of that is used by the "software" for fuel control. There are other "little" things like transport lag time ( how long a change in pulse width will take before it is burned and sensed by the O2 sensor) that also affect how FUEL CONTROL reacts to the sensor.

If you are beginnig to see the FUEL control software is not only VERY complicated in it's response from the O2 signal, it should also be clear it is very sensitive to the "REAL" 0-1 volt or MORE correctly 0000 to 1000 milivolts of input to the system. To alter that siganl means all those calibration values used by FUEL CONTROL software are also "no longer correct" for the false signal after a Xied or Vied skews the voltage.
(the Xied not only skew the voltage but change the resolution of the SIGNAL. It is that change in range of the signal that will defeat many of the calibrations that are trying to control fueling during closed loop operation!)

Is it any wonder they ( Xied and Vieds) set check engine lights. All of those fuel control inputs are monitored to decide if the system is working correctly, when it is not "other modes" are in affect. It may be as simple as going open loop, or as complicated as going very intrusive for an error code and further changes to A/F ratios over time!
Skewing the O2 sensor signal is a VERY POOR substitute for real "tuning."

I will edit this to add, remember the "skew" in sensor voltage is ONLY the O2 sensor part of the signal. The actual switch point as calibrated in the software is NOT changed with these devices ( unlike the SERT way of shifting the bias voltage!), and those range above and below the switch point is important in allowing the "Proportioan" and "Integral" fuel corrections to function properly!

 

The 14.7 stioch is the ratio that makes the least emissions. The best performance for a four cycle engine is 14:1 and 13:1 even 12:1 at wot.

Who gives a flying fig about the converter? They are taken off very soon after buying by most.