A Momentary Loss of Electrical Coordination

[Sven]

Wierd thing happened on the way to work this morning.  Coming up to a 4-way stop, I was slowing, when suddenly the engine stopped, the instrument panel lighted (with needle sweep) and the clock rest to the default 1:00.   For some reason, a momentary lack of electricity.  I was still rolling, so I hit the starter and accelerated to the stop sign.

WTF?

This is the same way I go every day, and I didn't hit a huge hole in the road.  The previous day I put 250 on running up and down the MRT...a few days before I rode 475 miles, and a few days before that, 375 miles, with some in-and-around riding between all those longer rides.  So, a 1,000+ miles over the week, and no other problems.

I'm just glad it didn't happen while I was making a left turn in front of on-coming traffic.

Anyone have something like this happen?

<A momentary loss of muscular coordination, a few extra foot pounds of energy per second...>   

[pmackie]

Hey Sven

Look around under the seat at your battery connections. It's possible that you could get this from a brief "dead short" across the battery.

[Sven]

Yeah, I did that when I got home tonight, when the same wierdness happened twice as I was trying to leave the parking lot at work.  I also checked the fuses (including the main fuse near the engine) and the connection to the starter motor.  I also lubed the switch at the sidestand.  When the sidestand spring gets gummy from oil and chain lube, the sidestand doens't snap all the way into place.  In this case, I think the sidestand is working fine, but maybe the switch is interfering with operation?

[pmackie]

Either the side stand switch, clutch switch or the handlebar switch could cause the system to cycle through a full power down off then on, if they short.

I'd be looking at the ignition switch and connections next. Any chance you added a connector for a heated vest or GPS, or anything else connected to the battery that might be shorting out?

As you found out, if it happened once, it will likely happen again.

[Sven]

I din't change nothin'.  But the clutch switch is an interesting candidate since there's a good chance in all three situations that I was pulling the clutch lever at the time it occurred.  (Slowing down at the 4-day stop, upshifting in the parking lot, downshifting at the guard gatehouse.)  You might be on to something!

[Sven]

Tuesday night I lubed the heck out of the clutch lever switch.  No problems since then.  So I'm hoping that was indeed the problem, although it's annoying to believe that while shifting, the clutch lever could actually cut electrical power.  Seems like a real liability.