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Discussion Starter · #1 ·
I have a 95 Monster and just put a new Battery in it about a week ago. We road to Rocky Point no real issues but a few days after I got back my bike died and wouldn't start. I got a jump and it would start, but if I pulled the jumpers off, the lights would dim and it would die again shortly after. I trailered it back home and just wondering what you guys think. Did the battery go bad already or is there a charging problem. What should I be looking for?

Thanks
 

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First, charge the battery. Then load test it, and/or check voltage at the battery terminals with the engine running at about 3000 rpm. Should be at 13.5 volts or better. 13.5 and your charging system is ok. Also check battery connections and ground connections.
 

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64duc said:
check voltage at the battery terminals with the engine running at about 3000 rpm. Should be at 13.5 volts or better. 13.5 and your charging system is ok. Also check battery connections and ground connections.
This would tell you your R/R is probably ok, I don't think it necessarily eliminates problems with your alternator.
+1 on the connections and grounds.
 

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Once you get it running it should run off the alternator even if the battery's bad. Right?

So there must be a problem somewhere in the charging system. (Be it the alternator, regulator, wiring, etc. I'm not sure.)
 

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Rameses said:
Once you get it running it should run off the alternator even if the battery's bad. Right?

So there must be a problem somewhere in the charging system. (Be it the alternator, regulator, wiring, etc. I'm not sure.)
Yes it should. The problem with using that as a diagnostic tool is pulling a battery cable on a running bike can damage the regulator and also take out expensive electronic components.
 

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howie said:
Yes it should. The problem with using that as a diagnostic tool is pulling a battery cable on a running bike can damage the regulator and also take out expensive electronic components.
I wasn't saying to unhook the battery while it was running. I was just saying that it should indicate that it's not the battery.

And wouldn't pulling the cable off while it was running immediately shut the engine off?
 

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Rameses said:
I wasn't saying to unhook the battery while it was running. I was just saying that it should indicate that it's not the battery.

And wouldn't pulling the cable off while it was running immediately shut the engine off?
In the days when cars had DC generators (yes, I am that old) a "shade tree" diagnostic was to disconnect the battery with the car running. As long as the charging system had enough output for the ignition system the car would run. GM actually approved this method as a rough test when alternators came out only to discover the voltage spike would sometimes kill a diode or three in the alternator.
 

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Discussion Starter · #9 ·
Ok, I fully charged the battery and checked it before I started it, after it was running and with bright lights on and with higher rpm. Always the same just around 12 volts (12.2 to 12.6) I did some more checking through wires and found a crispy one and it pretty much came apart when I messed with it more. I goes from the front wiring harness, right to ground on the left side of the bike. So after I get that replaced. I will start checking it again.

Thanks for the tips and advise, also should it be 13.5v when running?
 
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I've got similar problem this morning. Yesterday, I installed a battery tender.
This morning, I started the bike, run for a few second and die. Restart die again.

As I put the battery tender yesterday, I guessed the problem could come from the new cables hooked to the battery terminals. I remove it, try to start again and everything is fine.

My conclusion is that the new connectors created enough resitance to create a problem.
Do not forget, the engine run on alternator above 2,500 rpm (something like that. Bellow it does not have enough juice to maintain the engine running.

Try to clean your connectors with a wire brush and check your ground cable. It is the most important cable in the ignition circuit. Upgrading it is a easy improvement. Many poeple change the coil and keep the crapy cable.
 

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On several bikes I had a bag ground wire to batt. connection.
Also had a bad volt rectifier that sounds very similar to the original.
Anyway- once baby was born, there was plenty of vasaline around to smear on all the batteries' posts. For some reason- I read not to use Silicone grease here.
 

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Discussion Starter · #13 ·
I replaced the wire from the ignition to the ground (the one that was crispy) and now everything is working fine and when I bring the RPM's up it's around 13.5 [thumbsup]

Thanks for the tips and advise.

Larry
 
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