Good evening, I have an 05 FLHTCUI ultra classic that will die (quite a bit) during a ride, but start immediately upon cycling the run off button while I’m still rolling in gear.

Radio stays on, seems to only be killing ignition. I pulled a Po1353 and 1356 (no ignition front jug or rear jug, respectively). Bike runs perfect t otherwise. No alarm system

im thinkin the tip-over sensor, or a relay that gets reset after cycling the run stop switch on the handlebars.

thoughts?

 

Go tip your bike over. I think it will say tip or such on screen, Also guessing, the tip sensor told your bike to stop, it wouldn't throw a code.

 

I spoke to the owner who says the bike has fallen over to rest on the crash guards (foot washed out in a parking lot due to loose gravel) and the bike stayed runnin. He says he didn’t notice any lights on the dash.

I can’t get it to cut off by laying it over on the guards,
it only does it while riding. Seems to idle in N fine. Maybe fuel hose in tank??

 

Why would loss of gas cause loss of spark? Assuming codes are clue. I have tipped bike over many times, and it does seem tilt is erratic. Though I also think you reaction is to turn off , and not always paying attention. So one time I did it see, and it did say tilt. Point is, not sure it bank sensor.

I did have issue with houses when half full on my 2007. Only did half full. Not that, is a guarantee.

Is he restating with ignition switch or kill switch? Though bad kill switch should not throw a code, I would think. But would have lights on with engine off. But I think lots of things could be causing this.

 

did the 05 have the circuit breaker under the seat? my 2001 ultra would do that and got worse to where i had to sit on the side of the road for a few minutes to be able to restart.they are cheap enough to try

 

I am pretty sure it has a main fuse. But he said the radio would be on. So electric is not cutting out He is losing spark or fuel. Codes say spark, according to him.

 

it restarts immediately upon cycling the kill switch on the bars. It’s weird as hell.

 

I suggest something entirely different as the root cause...Dirty/sticking IAC.
Crankcase venting goes straight into the intake behind the filter and gets the intake assembly all gunked-up over time.
If the AC assembly hasn't been off for a while, then I strongly suspect this to be the culprit.

Pull the air filter assembly off and look at the cleanliness of the butterfly flap and surrounding areas/surfaces inside the intake throat.
Then shoot a lot of MAF cleaner (or similar) into the hole on the roof of the intake throat.
That shoots cleaner all around the IAC plunger/spring.

If the above is at fault, then the engine will often hunt for idle and die after coming to a stop. It will restart as if nothing happened.
It will not do this if you simply start the bike and let it idle.

 

I have a bit of experience with dirty iac. For me it stalls when coasting to stop. Also usually was a warning, where idle would dip and bounce back when coming to stop

 

Try flipping the RS switch on and off a number of times with the ignition off. Could be a flaky switch?

Might also be a flaky system relay and the it happens quick enough that it's not caught and an error?

Generally there will be other codes if it's the system relay..