ok, here is a resistive cable that connects between the 02 sensor and the existing o2 sensor cable. The device claims to lower eng temp by 20 degrees. But, in understanding how and o2 sensor works, the claim doesn't seem possible. an O2 sensor sends a low voltage during a rich fuel condition (.3 to .5 volts) and sends a high voltage during a lean fuel condition (.5 to .8 volts). So basically, you need the ECM to recieve a lean signal condition so that it will richen up the fuel mixture. That requires a device that can boost the voltage a little. assume mixture is lean, and volts is at .8, if the device can add another .1 volts to the .8, the ecm will see .9 volts and richen up the mixture to drop the voltage to .8 volts. Once at .8 volts, bike runs cooler. but the fact of the matter, the actual voltage is .7, the device is adding .1. So in the case of the resistive device. Actual voltage gets dropped. ecm thinks the mixture is rich, ecm leans the mixture even more, temp actually goes up. comments

 

Buy a power commander and don't worry about it. I let the Engineers do their job. I just ride baby ride.

 

Firstly , the o2 sensor is a voltage generator.
The newer o2 sensors have a heater in them to make them read more accurate and faster during the drive cycle.
The o2 sensor generates from 0 volts to 1 volt by chemical reaction and heat.
Readings under .500 mv (half a volt) are considered lean , over .500mv is rich.
If you add a resister inline to make the reading a little tiny bit low , the computer will add fuel to bring it up to .500 plus or minus.
The computer is being lied to in a calibrated way by the resister.
A slightly richer fuel mixture will cool the engine and drop the temps by possibly 20 degrees more or less.
If the original mixture was "too" lean , the engine will make more power and run better as well as cooler , the mileage can improve also.
This is basically how the IED and others work.
Mick

 

Do a serch for xied's, they are the same thing and you will find out more but Mick put it into perspective, I run the xied's on my 08 SG and they work.

 

if that were true then yes, adding a resistor would richen the mixture.

but everyone on the internet has the math saying 0 = rich and 1 = lean. so are we saying harley's 02 sensors work the opposite of all other o2 sensors in use today?

 

that is basically the same thing as the ieds. you can do a search for them on here, lots of info. some folks have them with no problems, some folks report throwing a cel. some say improved throttle response, others say no difference......

edit: what they said ^..... they replied before i did and i had the window open.

 

It is true. Lower voltage is leaner. For example, 200 mV is quite lean while 800 mV is rich. Ideal or stoichiometric is right around 450 mV. So technically 500 mV or .5 volts is to the richer side of stoichiometric. Not everyone on the internet says low voltage is richer... only those that don't know what they are talking about. You can't believe everything you read on the Internet. Plenty of misinformation.

This is a pretty good link if you really want to know more about Lambda sensors (O2 sensors) than you ever wanted to know.

http://en.wikipedia.org/wiki/Oxygen_sensor

Xieds that were mentioned and I presume these things you linked are nothing more than resistors that reduce the voltage signal from the O2 sensors to fool the ECM into thinking there is a false lean condition, thus causing it to richen the mixture to compensate. The result of this will be a cooler running engine and probably lower fuel mileage. Keep in mind that they only work when the bike is in closed loop mode and using the input from the O2 sensors.

 

ok, sounds good, will break out the Digital volt meter tomorrow. I'm headed towards the wide-band o2 sensors and want to make sure I understand the fundamentals.