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Bike wont start after tail light change!

fleetingyouth

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Ok I changed my tail light yesterday and it was a huge pain cause of my custom tail tidy. I tested it several time with ignition on but not the motor running before puting the bike away. I just went out to take it for a ride and it wont start .

All lights work. Display comes on. If I hit the ignition I hear a click from the frunk. If I grab the brake the display goes out then comes back on. Also the front running lights flicker when I hit the ignition.

I'm guessing this is an electrical problem? I used the stock incadesent dual bulb as a replacement. No wiring has been changed from stock. The break light is working fine.

Ideas?

Thanks
 
+1 on the battery vote. Put a charger on the battery and charge it. You can use a volt meter to see if it is charged. Should be around 13.1 volts.

Sent from my SM-N960U using Tapatalk
 
I concur with those thinking a discharged battery. Possibly could be a loose connection at the battery terminals but since you had the ignition on for awhile while changing the bulb that sends up a red flag.

The battery is small to begin with and doesn't have much reserve to allow leaving the ignition on while working on or checking things. If the battery has a few seasons on it it has even less reserve.
 
Thanks for all the replies.

I agree about the battery.

My real concern is what the cause is. The battery has been fine up until this point. I tested the break light long enough to see it work and then turned it off. So I dont think That was it. The battery is getting old so I'll just replace it but I dont want there to be a bigger issue that will just show up somewhere else.
The tail light just went out now the battery is acting up could there be a bad ground or something with the electrical causing an issue?
 
Thanks for all the replies.

I agree about the battery.

My real concern is what the cause is. The battery has been fine up until this point. I tested the break light long enough to see it work and then turned it off. So I dont think That was it. The battery is getting old so I'll just replace it but I dont want there to be a bigger issue that will just show up somewhere else.
The tail light just went out now the battery is acting up could there be a bad ground or something with the electrical causing an issue?
Charge it up and see if bike acts normal. Dduelin is correct in stating that an old small Motorcycle battery has little reserve. Especially if the bike had been sitting for a while.
Check out battery-stuff.com.
Good prices. Quick shipping too.

Sent from my SM-N960U using Tapatalk
 
Thanks for all the replies.

I agree about the battery.

My real concern is what the cause is. The battery has been fine up until this point. I tested the break light long enough to see it work and then turned it off. So I dont think That was it. The battery is getting old so I'll just replace it but I dont want there to be a bigger issue that will just show up somewhere else.
The tail light just went out now the battery is acting up could there be a bad ground or something with the electrical causing an issue?

Batteries can go bad basically overnight...My last replacement...I rode all over the place on a Friday...commuted to work, after work, rode bunch of places and stopped numerous places...on way home, rode the super slab...went out the next morning and battery went click click click...charging it did no good--charger stated fully charged after an hour but click click click (nothing left on over night)...bought a new battery and everything is good (that was 2 years ago).
 
Hi everyone,
I wanted to update this instead of starting a new thread.

After my last post, I had the battery tested as fine so charged and rode it a little more to see if it would happen again. Eventually, it did and was left stranded in the middle of the night.
So Bought a new battery since I was old and that was what everyone suggested. I live in Boston so with the shutdown, I didn't get around to installing it till last month.

Everything went fine till today, went out to the bike and it's dead again. So something is causing the battery to drain but it seems to be random not consistent.

The only electrical work ive done on the bike is to switch to LED lights on the rear blinkers. They weren't wired in they are stock plug connectors.

What could cause the bike to drain while off? Could it be a bad ground?
 
What could cause the bike to drain while off? Could it be a bad ground?

Do you have a digital multi-meter that reads current ("A" or "amps setting")? If so, you can test for parasitic drain by taking off the ground (negative/black) terminal, and connecting it in series with the meter. You should have < 50 mA of current with everything off. (< 5 mA is more ideal)

PSA - DO NOT TURN ON THE BIKE OR ATTEMPT TO CRANK IT WITH THE METER IN LINE. At best, you will blow out the fuse on the meter, at worse you will melt it or start a fire.
 
Ok I charged the battery fully last night with no issues. Connected it today and tested for draw. I got between0.0 and 0.12. So there doesnt seem to be anything drawing at the moment. Also tested the drain on starting the bike with no issues there and it is at 14.3 while at 4k rpms so it seems to be charging fine.
The only thing I can think of is something is draining the battery randomly only every once in a while.

I read on the forum some people having issues with battery and the ignition switch could that be possible? or could it still be a random bad ground?
 
Ok I charged the battery fully last night with no issues. Connected it today and tested for draw. I got between0.0 and 0.12. So there doesnt seem to be anything drawing at the moment. Also tested the drain on starting the bike with no issues there and it is at 14.3 while at 4k rpms so it seems to be charging fine.
The only thing I can think of is something is draining the battery randomly only every once in a while.

I read on the forum some people having issues with battery and the ignition switch could that be possible? or could it still be a random bad ground?
When you said you measured 0.0 to 0.12, what are the units? Amperes or milliamperes? 0.12 amperes would be a significant draw over several days.

I don‘t know what you mean by “testing the drain on starting the bike”. Can you explain?

Bad grounds, such as resistive or open, do not cause parasitic drain on the battery.
 
Hi Greg, I'm using an old meter with the text fading and I don't have a ton of experience using it this way, but I believe it is 0.12 milliamps. Its set to the 20m under the DCA section with the red lead plugged into mA port. Does that sound right?

What I meant was I tested it on load when starting the bike with no significant drop.

What are the chances its related to the stator or R/R? I was thinking of testing them next but it seems more likely its something draining the bike but only occasionally. Like every couple of months. Could it be related to something like the ignition switch or kickstant shutoff switch and only happens occasionally?
I'm also still thinking its related to the wiring on the tail light assembly since that is what started it all.
 
To test the resting draw you need to disconnect the red wire and run the multimeter between the battery terminal and the wire while disconnected and the ignition is off. You cannot do this while starting the bike, it would fry the multimeter. There are ways to do it involving putting a resistor inline, but we'll postpone that for another day. Any battery shop can test the battery for proper discharge amps.

I would check:

1. Resistance to ground from the new light input. This problem started after you messed with the electrical system. It stands to reason that the most likely place to have a problem is with what you changed.

2. Tightness of your battery connections.

3. The rest of your charging system. If your charging system isn't working then even a new battery will discharge to empty. Use the guides here: https://www.electrosport.com/pages/technical-resources.

If trouble persists I'll get out the service manual & let you know what it tells us to do.
 
This is an old thread where Beemerphile described a very similar problem and his solution.
 
Thanks for the replies. Harvey I'll read that thread thanks.

I was on and off the bike all day and tested the battery with the meter the whole time. Based on what people are saying here and other forums ive read its one of two issues. Parasitic draw or a charging issue. However, either one must be intermittent as it has happened 3 times since nov.
Ive tested the battery several times the last couple days for draw and if I am reading the meter correctly as I described above I am only seeing 0.12mA. The battery shows its charging fine when revving between 3-4k RPMs. The battery is fully charged . Both of these I tested several times on and off the bike today to see if there was any change.

I'm going to try and test the R/R and stator this weekend when I do the tires. I will also test the blinker but I havent altered the stock wiring in any simply replaced the bulb. I suppose there could still be a loose wire or something but with the bike off could a blinker drain the battery?

I suspect finding something that is intermittent will be very difficult for now I'm riding around with a spare battery.
 
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