Seca 550 just died at stoplight: voltage issue or electrical gremlin?

Hi folks, I recently got my 82 Seca running and have put around 100 miles on it in the last few weeks. These 100 miles have been trouble free.

First, it’s important to note that I have a four cell XPS anti-gravity battery.

Yesterday, my bike took longer than normal to start…I ended up having to jump my Seca from Honda. It finally got going and off I went. About 5 miles later, I pulled up to a light, idled for a minute or so, then the bike completely died all at once…not like sputtering to a stop… it just quit abruptly. Trying to start it again resulted in nothing. Not even a click from the starter solenoid. I did notice that my high beams were on, unintentionally so, and thought this may have been a factor. Push starting also did nothing. Luckily someone was with me and was able to go home and get the jumper cables, and we were able to get the bike going again without issue. Also, after jumping it time number two, I disconnected my headlight so that I didn't have any extemporaneous load on the bike so that I could limp home without further problems.

My hypothesis is: the hard starting and needing the jump the first time took the battery way down. Then after riding for 5 or so miles with the high beams on ended up not allowing the charging system to get the charge the battery back up so it ended up killing the ignition….? But if this was true, I would think that I would have heard something from the starter solenoid—at least a click of some sort… After I got home, I parked it, frustrated, and didn't fool with it until this morning because I thought I killed my anti-gravity battery.

Fortunately, after checking this morning, my battery had 12.5 volts and it immediately fired right up when I cranked it with the starter.

My question is, does my hypothesis make sense? Or could something else like a faulty side stand switch possibly be a part of this? Or something else entirely? I’ve never checked the voltage on the bike at idle with a multimeter though the gauge would show < 12 (don’t really have a lot of faith in the gauge accuracy-wise.)

Thanks for any suggestions.

 

Check voltage at the battery posts with the engine running. You should see 13.9 volts or greater at 2,000 RPM and above. If you see less than that you have a problem with the charging system Report back so we can help.

One thing that may be a clue is that it would not push start. This could indicate a fault with the safety circuit. I won't go down that road just yet though.

 

As Moe stated voltage output should be 13 + on any machine . they will shut down if bike does not meet minimum design voltage
And check all ground wires to battery and wire harness. Common problem with 30 year old bikes and corrosion or if things have been removed for painting

 

Have you replaced the original fuse box?

Gary H.

 

that battery might have a self protection circuit to shut itself off rather than go so low it hurts itself. that could be why you got no click at all when it stalled. but it should have not gotten that low, do the fuse box, charging circuit stuff

 

could be the battery, could be the regulator, usually reg's fail and there's uncontrolled power, but sometimes they can fail in a way that doesn't let power through...........

I'd say check your fuse box and relays first, though.

Then check to see if you have any wires shorting out.

Dave F

 

Sorry for the delay in getting back to this. The voltage at 2,000 rpm is between 13.25 and 13.35.

I read through the (clymer) manual and started going through the checks. First, I clean all the terminals on the reg/rectifier connection. I checked the resistance between the three white wires. I only had a .5 ohm reading with one set. The other two did not register.

I also checked resistance between green and brown wire and found between 8 and 8.5 ohms.

I did not go through the reg/rectifier tests because I only have one multimeter at the moment.

Lastly, I did peek in under the stator cover and the brushes have plenty of extra life before the limit lines.