Need quick insight guys!! Please! its drivin me nuts Help!

[mark8]

On a fully charged battery, I only get about 2-3 rides out of my 97' 916, then the battery drains so low that I cant even start it. I dont know if its the right tool, but I put a multitester on the battery when it was idoling and it was totally frozen steady!!, even when I reved it all the way up to 4000 RPM. I heard on here that this would mean a bad regulator. It was in the shop getting serviced at a credible Ducati Dealer and they said the electrical system checked out fine! I'm bringing the bike back there this weekend for more testing (under no charge). I need to know what really is the problem if they say the same thing again. Is it a bad battery?, bad regulator?, generator issue? I had the battery on a trickle charger for about 20 hours and the light stayed red!! I hooked it up to another trickle charger for a second just to double check and the light was solid green! I heard a bad battery will get overcharged by a trickle charger to compensate for the loss of cells. I heard this can ruin trickle chargers! From what happened with the tickle chargers, it definitely sounds like a bad battery. Any help would be so appreciated!! I have looked on here a lot and found tons of information on similar issues, nut I still cant put my finger on it!!

[jbcaddy]

my understanding is that if the voltage does not rise with the RPM then it is a charging problem

[amullo]

Probably the generator connector.

See my write up
916 - 748 Charging problems - easy fix

//AMULLO

[mark8]

I appreciate your feedback. I am still learning about these poorly designed charging systems. How would you know its probably not my battery or regulator. You said in your write up if its a stable reading when idol or revving, then its regulator. You replied to me saying generator. I'm a little confused about this. I wanted to tell you another symptom. The last time I rode it, half way through the ride it died out on me!! It started losing power, popping from exhaust, then finally shut off. I waited about 10 minutes then had to bump start it. Luckily I had enough juice some how to make it home, but the power was weak and inconsistent. Is it possible to get the bike right?! and not have any electrical problems no matter how long and how many times I ride it!? Its really getting frustrating. I would pay hefty to somebody that could fix this problem for good. This is such an unbelievable PITA!!!!!!!!!!! Do you ever have this problem anymore with your bike? I really appreciate your time. Do you know anyone that could fix this for me in the New England area? My Dealer even said everything was good!! But it obviously isnt.

[quack2]

Try replacing the rectifier. My 748 did the similar thing, I would charge it and once I put it in gear and released the clutch the thing just died. I would try to start it and no dice. Had the rectifier (right hand side near the horizontal cylinder) replaced and the problem went away.

[mark8]

Thanks for the help! Is the rectifier the regulator? Both terms refer to the same 1 piece right? You are saying to just get a new regulator? All you did was replace the regulator and you never had any battery or bike dying issues again?

[mjfrank]

One in the same.

It's worth it to pull the battery mount off the frame and check the two yellow wires coming from the alternator. These have a cheap connector on them, and due to the amp load, will melt the wires. Sometimes you can cut them back and just solder the reg/rec wires directly. Unfortunately on some bikes, the wiring gets toasted all the way back to the stator coil. (which would require removal of the left side flywheel/alternator cover to fix.)

Usually it's the Reg/Rec though.

--Mike

[tye1138]

Just to let you know, my bike is doing something very similar... its a bad battery in my case, its over 4 years old!!!

[748Rider]

Originally Posted by mark8

I appreciate your feedback. I am still learning about these poorly designed charging systems. How would you know its probably not my battery or regulator. You said in your write up if its a stable reading when idol or revving, then its regulator. You replied to me saying generator. I'm a little confused about this. I wanted to tell you another symptom. The last time I rode it, half way through the ride it died out on me!! It started losing power, popping from exhaust, then finally shut off. I waited about 10 minutes then had to bump start it. Luckily I had enough juice some how to make it home, but the power was weak and inconsistent. Is it possible to get the bike right?! and not have any electrical problems no matter how long and how many times I ride it!? Its really getting frustrating. I would pay hefty to somebody that could fix this problem for good. This is such an unbelievable PITA!!!!!!!!!!! Do you ever have this problem anymore with your bike? I really appreciate your time. Do you know anyone that could fix this for me in the New England area? My Dealer even said everything was good!! But it obviously isnt.

I had the same issue, i would be able to ride, then when the bike got up to temp it would act strangely..... rev counter was going mad, hard to accelerate, then when using the indicator it would cut out completely.

I had it sent off to a Duke Dealer to check out the issue and one of the generator coils had popped, so there would be a conection when the bike was cold, as soon as the bike warmed up the wire would expand and create a short circuit, then the bike was running on the juice that was in the battery

[amullo]

Originally Posted by mark8

I appreciate your feedback. I am still learning about these poorly designed charging systems. How would you know its probably not my battery or regulator. You said in your write up if its a stable reading when idol or revving, then its regulator. You replied to me saying generator. I'm a little confused about this. I wanted to tell you another symptom. The last time I rode it, half way through the ride it died out on me!! It started losing power, popping from exhaust, then finally shut off. I waited about 10 minutes then had to bump start it. Luckily I had enough juice some how to make it home, but the power was weak and inconsistent. Is it possible to get the bike right?! and not have any electrical problems no matter how long and how many times I ride it!? Its really getting frustrating. I would pay hefty to somebody that could fix this problem for good. This is such an unbelievable PITA!!!!!!!!!!! Do you ever have this problem anymore with your bike? I really appreciate your time. Do you know anyone that could fix this for me in the New England area? My Dealer even said everything was good!! But it obviously isnt.

If the battery has a stable reading when idling, your have one of 4 problems.

*The connecting yellow wiring between the generator and rectifier/alternator has a short or have burned off (VERY common! what my write up discusses).
Fix: Solder them together again

*The rectifier/alternator is damaged (Can be checked by placing a voltmeter on the yellow leads from the generator to alternator/rectifier. When idling they sould read atleast 15volts AC and ~35 volts at 4500-5000RPM)
Fix: Buy new rectifier/alternator unit (The piece under the battery)

*The DC side of the wiring from the rectifier/alternator to the battery is damaged/off/shorted. You have a good AC current, but volts are still stable.
Fix: Check all the wires and see if they are damaged. Replace as needed.

*Generator burned out (Can happen but not very common). If you get 0 volts AC from the yellow generator leads.
Fix: Expensive replacement of the generator.


IF the battery volts are jumpy when putting a voltmeter on the batteryterminals, then you probably have a grounding fault. Check the wiring/connectors/fuses. Clean go from there.

Hope that helps..

//amullo