[firecaptp7]

 

[tenacres650]

battery terminals are most likely broken, same thing happened to me

[Mr.Mazza]

Fuel pumps will have a swirl tank at the bottom, and will literally near empty the tank.
Id check battery connections as it could be a fluke.

[pmanaz1973]

Battery terminals or sidestand switch is my guess.

[wildbill]

all positive answers to possibly a negative battery cable issue

[Arizoni]

firecaptp7

If the sidestand safety switch is still plugged into the main wiring harness, that would be my first guess as the source of the problem.

Some of these switches are installed so that the slightest movement of the sidestand will trigger them to shut off the engine power.

On a bumpy road, the moving sidestand could do exactly what you describe.

If you haven't disabled the switch, it is located under the sidestand.  Follow the wires back to the frame seat upright and you will find where it plugs into the main wiring harness.
Unplug it and tape the dangling ends to something like the frame.

Of course there is a warning here.  With the switch disabled, the bike can be started and run while the sidestand is still down.

Passing over a dropoff can cause the sidestand to knock the bike down so always check to see if it is up before you ride anywhere.

To answer the other obvious question, yes, you can run the motorcycle while it is resting on the sidestand if the transmission is in neutral.  The oil pump will continue to pick up oil from the sump.

Another "cure" for the "misbehaving misfire" is to replace the OEM Bosch spark plug with a NGK #BPR6ES spark plug.
Be sure to get the kind with a screw off cap on top because the high voltage spark plug connector slips down directly on the threads under that cap.
If you try to use a spark plug with the large metal cap still on the top of it, the electrical connector will not plug onto it like it should.  That will cause a lot of mis-firing.

[longstrokeclassic]

Alternatively it could be adjusted...
Mine came fitted so the slightest movement would make/break the circuit if it bounced off its rest position.
A quick adjustment involving two Allen bolts means now the engine wont cut out until its over halfway through its travel arc.
If the side stand ever bounces that far down during a ride it'll probably the last thing I'm worried about.

If mine starts to fail due to water ingress I'll remove it, until then I'll use the sidestand switch to cut the power in the ignition circuit instead of using the ignition switch contacts which are probably the more fragile of the two components.

[Craig McClure]

In my opinion the side stand switch is a problem waiting to happen. get rid of it before it drops you into a bad situation (loser town @ sundown)

[The Old Coot]

Mine did that and here's what I found. That's what's left of the negative battery terminal on the battery. The heat shrink on the cable kept it together enough so the bike would more or less run but it skiped and stumbled. 

[mattsz]

The heat shrink on the cable kept it together enough so the bike would more or less run but it skiped and stumbled.

This story has been told since the introduction of the UCE...

[tenacres650]

Mine did that and here's what I found. That's what's left of the negative battery terminal on the battery. The heat shrink on the cable kept it together enough so the bike would more or less run but it skiped and stumbled. 

+1 mine was the same as this