mine is engaged all the time. I believe that mother HD knew what they were doing and if the bike determines it's engaging then so be it.

 

On my '08, I need to have the throttle rolled forward at a stop to get it to engage. I don't know if that's automatic on the newer models or not.

The main reason I can think of to not have that engage is that the engine seems to be a bit starved for fuel if you need to get a bit of a quick start when that's running, and I've stalled mine out a couple times halfway around a left turn (not fun). With the roll-off on the throttle disabling this, I do tend to use it (especially in the summer) and when the light for the cross-traffic goes yellow, I'll let it go and give it a rev to get the rear cylinder really firing again, and there's no problem.

For stops that I expect to be fairly short, I just don't bother.

 

The manual states the process of enabling it so that it's on at bike's discretion.

 

The ETIMS (Engine Temperature Idle Management System) can be turned on or off by the rider on all touring models 08 and later, the 07 models have the ETIMS but the dealer has to hook in a external computer to turn it on/off. If you have the bike running and you are at a stop you need to ROLL the throttle forward and hold it forward while looking at the cruise control light in the tach, let the light BLINK GREEN 5 times then release the throttle, the ETIMS is then enabled. To disable follow the same procedure but let the cruise light BLINK RED 5 times then release the throttle. To CHECK if the ETIMS is on or off just roll the throttle forward for a few seconds if the cruise light is green then the ETIMS is on if it is red it is off. The heat sensor for the ETIMS is located in the rear of the front cylinder and the ETIMS will kick in when the bikes engine temperatures get to approx 290 degrees, the ETIMS will then turn off the rear cylinder to help slow down the over heating process. As soon as you give the bike some throttle the rear cylinder will turn back on and the engine will run on both cylinders.

 

Mine is on, only because I keep forgetting to disengage it. I have my idle set so low that when it goes to the single cylinder my bike dies sometimes when its really hot.

I disengaged my wifes, because it stalls when leaving a stop light on her and don't want her to get into an accident because of it.

 

The bottom line is you have the idle too low on both bikes. HD sets the idle higher (1100RPM) on the newer bikes because. 1- To keep the charging system up to the bikes demand & 2- to keep the oil pressure up so the top end of the engine gets proper lubrication. Setting the idle to low will only damage the engine and the charging system. The old school potato potato sound is cool but it is not good for the newer bikes.

 

+1 to what ironmark said. IIRC you don't want your idle to be under 950 rpms to prevent this damage. Oil pressure is much better on the 96/103 motors than the older 88" models. On my old 01' springer and my 05' RG the oil pressure gage would drop to almost 0 at idle when the oil temps got too high.

 

Mine has been engaged since the day I bought the bike. And it will stay that way. But I admit, it took me some time to get used to it. If you are at a stop and it kicks in. There is somewhat of a hesitation when you get back on the throttle.