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Let's Ride!!
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Discussion Starter #1
I don't know enough about bikes yet to be certain of how to diagnose this problem with my bike, so hopefully you guys can tell me what I need to check and then I'll get back to you with the results.

What happened: was riding the bike today to go about my business. Went to the local junior college, started fine for the trip there. Started fine upon leaving there. Made a stop, it started fine upon leaving there. Stopped at a gas station to fill up, and this is where it got weird. Put the key in the ignition, turned it to on, the dash lit up for about 5 seconds, then went out.

What I've done:
  • Fiddled with the key in the ignition; nothing
  • Checked the fuses; all good
  • Got a jump; bike started, but then once I removed the cables, it died again
  • Once I got the bike home, hooked it up to the battery tender; tender indicates >80% charge, but still no power to the dash

So what could this be? The only time the dash comes on so the bike can start is when I have it jumped to a car battery. But once I remove the cables, there's no power to anything, even with the battery being nearly fully charged.

I'm stumped. Help. :(
 

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Senior Member
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2,527 Posts
Probably not an easy answer, could be many things. I'd start with checking all your wires and pull the ignition switch. Sounds like a broken connection somewhere or possibly a bad ground. Also check the kickstand safety switch.
 

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Premium Member
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5,236 Posts
Probably not an easy answer, could be many things. I'd start with checking all your wires and pull the ignition switch. Sounds like a broken connection somewhere or possibly a bad ground. Also check the kickstand safety switch.
Sounds like a battery opening up under load,put you meter on the battery and check the battery voltage, should be around 12.6.Press the starter button and watch the meter if it drops to 0 or very low voltage the battery is opening up a connection inside.Th fact that it starts immediately when jump started makes me think battery problems.Sudden failures in bike batteries is not uncommon.

80 % charge also indicates possible cell failure in the battery and since these bikes need battery voltage to run,run off the battery and the alternator recharges the battery unlike most automotive systems.Plus it is easy to check.
 

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Linkmeister Supreme
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7,960 Posts
Are the battery cables both tightly attached to the terminals?

Were the jumper cable clamps somehow making better contact with the battery cables than the bike battery does?

Have you had the bike in storage for the winter and just recently started riding again?
Is it possible the battery froze and warped the lead plates inside?
Or are you able to ride all/or most of the year, and this no power to dash anomoly just blind sided you?

Seeing that it will start and run when jumpered off a car battery, but dies as soon as you disconnect the cable clamps, it must be one of two or three things IMHO.

1. Either the terminal screws holding the cables are loose, or cable ends are loose and somehow the clamps exert enough pressure to make a good connection, or

2. There is something wrong with the battery. Check voltage with a multi meter.

I had a somewhat similar problem last season that made me not trust the bike to get to work and home again. I commuted to work from May 11 until mid October until one day after work I had no dash lights when the ignition was turned on. (First day in weeks when it was raining :() Long story short--- unloaded all my gear from bike, pulled seat off and wiggled wiring harness. Dash lights come on, hit starter button, lights out again, wiggle harness, lights come on, after 3 or 4 repetitions the engine started and ran fine until I stopped for gas. Turned key off and fuelled up. Turned key back on and no lights. (Did I mention it was raining? [email protected])

Unloaded duffle bag and throw over sadlle bags again, remove seat, yada yada, yada,--- wiggle wiring harness a few more times, dash lights on, off, on again and finally starts. Reload w/o turning engine off and ride 1/2 mile, slow for red light and engine dies. Coast bike off road to parking spot and go throught the old familiar drill again. It was raining. Oh yeah, I already told you that. :)

Finally got the old girl home and parked her. Started driving the cage to work. Messed around with harness a bit before winter came in ernest, but never discovered which wire is loose or broken.

Got bike out one nice day in February and rode to bike night. No problems.
Got it out again last Friday and followed a friend around for 25 miles while he was practicing to get his mc license. No problems.

Still need to take bike over to shooting buddy and fellow rider who is a retired auto mechanic. He offer to help me go through the wiring harness to find the break/open connection.

Our symptoms are similar, but I doubt the problems are exactly the same.

You have to figure out what changes when the jumper cables are disconnected.
Is it physical movement disconnecting the circuit?
Or is there an electrical problem with the mc battery?
 

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Old Truck Junkie
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4,133 Posts
It is ussually the ground cable at the frame. The batt viberates and the cable becomes loose.
 

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Registered
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I agree with the others above Sounds like either a bad battery or a bad connection to the battery.

If the connectors are clean and tight, might be worth taking the battery out and to you local auto parts store to get tested. Most around here will test the battery for free to give you an idea if it needs replaced or not.
 

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Let's Ride!!
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Discussion Starter #7
Sounds like a battery opening up under load,put you meter on the battery and check the battery voltage, should be around 12.6.Press the starter button and watch the meter if it drops to 0 or very low voltage the battery is opening up a connection inside.Th fact that it starts immediately when jump started makes me think battery problems.Sudden failures in bike batteries is not uncommon.
When I posted this, the battery tender was flashing green, which indicates >80% charged. I just got back home and looked and it's now solid red, which indicates <80% charged. Checked the voltage and it's at 10.52. Can't check what it is when pressing the starter because there's no power to the system.
80 % charge also indicates possible cell failure in the battery and since these bikes need battery voltage to run,run off the battery and the alternator recharges the battery unlike most automotive systems.Plus it is easy to check.
That's interesting. Had never heard of such a thing.
Are the battery cables both tightly attached to the terminals?
Yes, disconnected and reconnected both.
Were the jumper cable clamps somehow making better contact with the battery cables than the bike battery does?
No.
Have you had the bike in storage for the winter and just recently started riding again?
Nope, just went up to Tacoma, WA 2 weeks ago.
Is it possible the battery froze and warped the lead plates inside?
Not likely, it's been cold sometimes, but the bike is in a garage so it's a little warmer than outside.
Or are you able to ride all/or most of the year, and this no power to dash anomoly just blind sided you?
Complete anomaly. Started fine to go to class, started fine leaving class, started fine leaving another stop. Stopped for gas, when I stuck the key back in and turned on the ignition, the lights came on for about 5 seconds, then everything died.
Seeing that it will start and run when jumpered off a car battery, but dies as soon as you disconnect the cable clamps, it must be one of two or three things IMHO.

1. Either the terminal screws holding the cables are loose, or cable ends are loose and somehow the clamps exert enough pressure to make a good connection, or

2. There is something wrong with the battery. Check voltage with a multi meter.
1. As stated above, they seem to be making good contact.

2. Also as stated above, just minutes ago it was reading 10.52. I did not take a measurement when I first got the bike back home.
I had a somewhat similar problem last season that made me not trust the bike to get to work and home again. I commuted to work from May 11 until mid October until one day after work I had no dash lights when the ignition was turned on. (First day in weeks when it was raining :() Long story short--- unloaded all my gear from bike, pulled seat off and wiggled wiring harness. Dash lights come on, hit starter button, lights out again, wiggle harness, lights come on, after 3 or 4 repetitions the engine started and ran fine until I stopped for gas. Turned key off and fuelled up. Turned key back on and no lights. (Did I mention it was raining? [email protected])

Unloaded duffle bag and throw over sadlle bags again, remove seat, yada yada, yada,--- wiggle wiring harness a few more times, dash lights on, off, on again and finally starts. Reload w/o turning engine off and ride 1/2 mile, slow for red light and engine dies. Coast bike off road to parking spot and go throught the old familiar drill again. It was raining. Oh yeah, I already told you that. :)

Finally got the old girl home and parked her. Started driving the cage to work. Messed around with harness a bit before winter came in ernest, but never discovered which wire is loose or broken.

Got bike out one nice day in February and rode to bike night. No problems.
Got it out again last Friday and followed a friend around for 25 miles while he was practicing to get his mc license. No problems.

Still need to take bike over to shooting buddy and fellow rider who is a retired auto mechanic. He offer to help me go through the wiring harness to find the break/open connection.

Our symptoms are similar, but I doubt the problems are exactly the same.

You have to figure out what changes when the jumper cables are disconnected.
Is it physical movement disconnecting the circuit?
Or is there an electrical problem with the mc battery?
That does sound very similar, though I had not tried jiggling the harness at all. Just did and it made no difference.
It is ussually the ground cable at the frame. The batt viberates and the cable becomes loose.
Nope, that's solidly connected.
I agree with the others above Sounds like either a bad battery or a bad connection to the battery.

If the connectors are clean and tight, might be worth taking the battery out and to you local auto parts store to get tested. Most around here will test the battery for free to give you an idea if it needs replaced or not.
That's sounding like a real possibility. The battery is only a few months old, so it'll still be under warranty.
 

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Premium Member
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5,236 Posts
You sound like you are on the right track,for all intents and purposes the battery is dead at 10.52 .At a little over 2 volts per cell on a fully charged battery.10.5 volts indicates a dead cell and I would do as you said and take it back to where you bought it and more than likely they will replace it.
 

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Let's Ride!!
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Discussion Starter #11
You sound like you are on the right track,for all intents and purposes the battery is dead at 10.52 .At a little over 2 volts per cell on a fully charged battery.10.5 volts indicates a dead cell and I would do as you said and take it back to where you bought it and more than likely they will replace it.
Sounds good, I'll give that a try.
Most Capacity Discharge Ignitions will not fire at 10v. That is why it would start when jumped.
Makes sense.
Is the charging system putting out? You should have about 14v at 4k rpm.
Not sure, haven't tried jumping it again to check that.

Also, last night as I was going to bed, I checked the tender and it was flashing green again, but this morning it's back to solid red. So I'd say there's definitely something wrong with the battery. I'll get a new one today and see what happens.
 

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Let's Ride!!
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Discussion Starter #12
Took the battery back to the place I bought it, they tested it and say there is indeed a bad cell. It's under warranty, so I just have to go back and pick up a new one.

Thanks for the help guys.
 

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Let's Ride!!
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606 Posts
Discussion Starter #13
Got the new battery, installed it, lights came on, and it started right up.

Now, to make sure it's not something messed up with my charging system, where's that info on how to test the stator output and the R/R function?
 

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Big Dumb Viking
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Let's Ride!!
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Discussion Starter #15
Oh duh, it was right at the top of the page! :doh:
 
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