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Let's Ride!!
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Discussion Starter #1
Hey guys, just trying to confirm my diagnosis of the problem before I buy any parts:

Symptom
Bike does not want to start after it has been sitting more than about 20 minutes

Notes
  • Battery shows 13.3V with ignition off, 13.0V with ignition on
  • When pushing the starter, the bike immediately sounds like it's out of power
  • The lead that goes from the (+) terminal to the starter solenoid shows evidence of overheating (the side cover is making contact with it and has melted some)
  • Bike starts up immediately with a push start
  • Volt meter shows 13.6V at battery when running @ 3K RPM
  • Bike runs with no problems once started

Diagnosis?
I'm going with the starter solenoid is failing.

Reason
I cannot find any shorts or loose connections. The fact that it runs and the charging system seems to be putting out 13.6V when running and the battery is fully charged prior to trying to start the bike is what leads me to this conclusion.

Do you guys agree or have another diagnosis?
 

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1986 VN750
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Question, how low does your voltage drop when you push the starter?
 

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Let's Ride!!
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Discussion Starter #3 (Edited)
I'll have to recharge the battery again to check. I just went to look and it was registering 12.7V with the ignition off, but then dropped to 11.9V when I turned the ignition on. Didn't even bother pressing the starter at that point.

And I don't think it's a battery issue. It seems to be taking/holding a charge just fine, but then it's getting drained when I try to start the bike.

I'll post again after it recharges on my battery tender.
 

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Diagnosis?
I'm going with the starter solenoid is failing.
Battery shows 13.3V with ignition off, 13.0V with ignition on
When pushing the starter, the bike immediately sounds like it's out of power
The lead that goes from the (+) terminal to the starter solenoid shows evidence of overheating
I would lean toward the starter dragging, pulling too many amps. But the voltage drop would tell more.

Could be the battery no longer has enough cranking amps. How old and what type?
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Let's Ride!!
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Discussion Starter #5
Battery is about 2 months old. It's a maintenance-free battery, but can't remember the brand.

So I charged it last night. Was showing 13.45V 15 minutes after I disconnected the tender. Left it alone all day. Just checked it now. Registered 13.1V with the ignition off. Turned the key to on and it dropped to 12.0V. Wow, didn't expect that. Didn't even press the starter button as there was really no point.

So now it's looking like there could be something wrong with the battery? This seems hard to believe though. Like I said above, it's only about 2 months old. AND I got this battery after the previous one developed a bad cell after about 4 months or so. Could I really have THAT bad of luck that I got two bad batteries back to back? Well, yeah, I suppose I could...

So battery, starter solenoid, or a power drain somewhere?
 

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Sparky!!!
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8,697 Posts
what kind of charger are you using? how many amps is the charger... how did you condition the battery when it was brand new out of the package? All of these could lead to a premature battery failure, but not 2 months quick.

even with the battery at 12.0 volts, try bypassing the starter solenoid by taking a screw driver between the two large posts. if the starter turns over normal then you have a problem in the start button, the solenoid, or the harness between the two.

Check for resistance in the start switch to make sure that the start button is not a culprit.
Next check the resistance between the two small terminal to make sure that the coil isn't broken (resistance here should be fairly high). An easier way to test the solenoid is to hook one small terminal straight to the battery positive, and the other to the negative, and then test resistance between the two large terminals. (Multi Meter should read 0.0 Ohms)
 

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Does sound like you could have a bad cell on the battery.
I'd pull it off the bike and take it to your local parts store to be tested.

Also, to test if it's the starter solenoid, try jumping the two terminals across it to see if the starter kicks in. this will in effect bypass the solenoid and should start right up if that's the problem. If that doesn't do it then it could also be an issue with the starter itself as stated above.

However, I'd still get the battery checked. I'm pretty sure you shouldn't be dropping voltage that quickly unless you have a parasitic drain somewhere.

Edit: And it looks like Slim beat me to the punch :)
 

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I'm with Ndr, take the battery in to have it load tested before replacing any parts.

Same brand battery as the last one? Let us know the brand if the battery is defective again. Dropping from 13.1v to 12v just by turning the key on is not a good sign for the battery.

New batteries can, and do, fail. It sounds like this brand is having a bad run of batteries, or is just no good overall.
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Let's Ride!!
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Discussion Starter #10
just wanted to throw this out there......check your frame grounds....you never know
Thought of that right away too. Checked them, they're fine.
I'm with Ndr, take the battery in to have it load tested before replacing any parts.

Same brand battery as the last one? Let us know the brand if the battery is defective again. Dropping from 13.1v to 12v just by turning the key on is not a good sign for the battery.

New batteries can, and do, fail. It sounds like this brand is having a bad run of batteries, or is just no good overall.
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Yeah, I think I'll go ahead and get it checked first. I'll update once I get that done.
 

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Let's Ride!!
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Discussion Starter #11
Think I may have found the problem when I pulled the battery:
http://youtu.be/fMqWWmy4c08

Now the question is: what would cause that to happen? And how do I make sure it doesn't happen again?
 

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1986 VN750
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Hah, glad you found the culprit!
 

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The battery has been hot, could have sulphated and shorted internally, left on a charger too long or charged at too high amperage, and not likely but the charging system on the bike could be charging too high.

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Let's Ride!!
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Discussion Starter #15
The battery has been hot, could have sulphated and shorted internally, left on a charger too long or charged at too high amperage, and not likely but the charging system on the bike could be charging too high.

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Not likely left on charger too long; I only put it on the battery tender if I hadn't ridden in a couple days and knew I was going to ride the next day. Shouldn't have been too high an amperage since it was a battery tender. Bike's charging system is putting out 13.6V just as the pros here say it should be.
Ithat its why I asked you about how you had charged the battery and conditioned it when it was pulled out of the box.
I did not charge it. When I brought back the other battery that had a bad cell, this was the battery they gave me and they said it was all charged and ready to go. Just put it in my bike and started using it.
 

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Oh it doesn't bulge like that to hold it in place better? :D

My kids have one of those pocket rocket electric scooters. They used to do all kinds of crazy charging on that poor battery..short charging...leaving it on all night...etc. When it stopped working and I went to take it out I could barely get it to wiggle out of the holder it was so bulged and deformed.
 

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I would have to say the battery shorted internally then. Something had to create the heat to deform the case.

I reconditioned and sold thousands of auto batteries, heat and freezing completely solid are the only things that do that to battery cases.
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Premium Member
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You mentioned that the positive cable connection to your solenoid showed signs of getting hot and your side cover had a melty spot. Have you pulled that connection off and cleaned/dielectric greased it? You probably should pull, clean and DE grease all your connections just to be sure if you haven't or it has been quite a while, especially the grounds. Corroded connections get hot and I'm thinking something had to cause your battery to short internally...
 
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