I have a 2008 ultra with 12,000 miles, I went for a ride today and when I stopped to get off the bike to open the garage door the engine sounded like it was runing on one cylinder and a noise was coming from the primary that sounded like an air pump noise.

I pulled the plugs and they look perfect ( they only have some where around 500 miles on them.

I will more that likley take it to the dealer tomorrow.

Any ideas

 

Was it pretty hot and the "parade mode" kicked in if you have it enabled?

 

+1 That was my first thought.

 

Also my guess...I haven't heard if they can inadvertantly activate if it's not too hot. Hope and pray that's all it is. If that's the case, some throttle should shut it down and return the engine to normal (both cylinders). Good luck

 

Thats what I thought, it sounded just like it however it is turned off and the bike had only been riden 30 min or so. The temp was only 75 degrees out at 6 pm.

I think I will start it up this morning and see if it sounds like it did last night when the bike was warmed up, and go from there

 

Started the bike this morning and it shounds like it always does, I took it for a ride and it appears ok. I filled the tank 93 octane (I was down almost 5 gallons) Bike runs gooood and sounds gooood.

Don't know what the sound coming from the primary was last night but it gone.

 

Good to here. My bud's UC will go into parade mode on a 75 deg day if we are moving slow or are in stop & go traffic.

 

I'd still vote "parade" mode. Noises like you describe don't just go away.
Glad everthing is ok.