I have a 2011 FLHTCU. A friend has a newer FLHTC and said that at idle if you rotate the throttle back past the normal idle position it will shut off fuel to the back cylinder. I tried this on my 2011 and a orange light came on. Releasing and turning back again a green light came on. Lights go out when throttle is released. What is this doing to the bike?

 

It activates and deactivates the heat management system or something similar in name. It only shuts off the fuel to the rear cylinder when stopped and the engine is at a certain temp. I'm sure someone will chime in with a more detailed and scientific explanation. The orange light means you turned the system off and the green light indicates you have turned it on.

 

Thanks!

 

Thanks actually a pretty good explanation.

Assuming the bike has the system activated via a check box within the ECM program, the throttle can be used to engage/disengage the heat management system.

And like you said, if the motor gets to a certain temp under low to no speed conditions, the rear cylinder begins to "skip fire." And as temps climb, the fuel is completely cut of to the rear cylinder causing it to pump cooler air through the chamber and lowering the temp.

The stock HD system has its own set of parameters for when the heat management system starts. Other tuners may have their own parameters requiring temps to be at a different temp before engaging.

Hope that helps.