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The battery is brand new and it is definitely not being overcharged. I can trickle charge it over night and it'll run for a couple days just fine.

I'll try that troubleshooting chart the next time I make it back to my parent's place - thanks!

Branton

The battery is brand new and it is definitely not being overcharged. I can trickle charge it over night and it'll run for a couple days just fine.

I'll try that troubleshooting chart the next time I make it back to my parent's place - thanks!

Overcharging has the same effect as undercharging. The battery will lose its charge and the bike will not start. I went through three different batteries and three different dealers before I decided to figure out what was wrong with the bike myself. Turned out to be bad regulator rectifier. I was getting 17.5 volts on testing and it was cooking all of the acid out of the battery.

brian12 wrote:

The battery is brand new and it is definitely not being overcharged. I can trickle charge it over night and it'll run for a couple days just fine.

I'll try that troubleshooting chart the next time I make it back to my parent's place - thanks!

Overcharging has the same effect as undercharging. The battery will lose its charge and the bike will not start. I went through three different batteries and three different dealers before I decided to figure out what was wrong with the bike myself. Turned out to be bad regulator rectifier. I was getting 17.5 volts on testing and it was cooking all of the acid out of the battery.

Well, hell. What's funny is that I keep thinking that I have half a clue!!

shuffled on over to the Garage.

I hope you get everything sorted out.

Thanks! It's going to be a couple days before I can borrow a torque wrench to get the rotor back on properly. But then I'll do the tests that brian12 pointed out to me.

Branton

I've seen this happen on a number of occasions.
The battery is dead, gets jump started from car, generator puts out max output for extended period and fries regulator.
One diode in rectifier fails and batter still isn't charged.
New battery fitted which goes flat due to discharging through stator windings because of faulty diode in rectifier (which overheat and cook insulation) Second battery fails.
Bike goes into shop for checks.
At least you don't have to get a wiring harness as well (check all the block connectors)
Personally I haven't used the company you mention but quite often aftermarket stuff has superior insulation and components (they are not production parts, made to lowest cost to ge job done)
PJ

Okay, I was able to "borrow" a torque wrench from O'Reilly's last night. I had to pay $180 and I'll supposedly get it back when I return it. And I better or else my landlord will not be happy when his check bounces

Anyhow, I got the rotor back on and was able to go through the diagnostics at http://www.electrosport.com/electrospor ... nding.html

When I got to the part of measuring voltage coming out of the three yellow leads on the stator while running at 5k rpm, I was hardly getting 0.02 V from each and should have been getting close to 50 V. So, it seems my stator is definitely bad. Combine that with the fact that half of it looks sort of fried, I'm satisfied with the test. The tests I was able to do on the voltage regulator/rectifier seemed to pass, even though the dealer told me it was bad.

I have a question though. At the very start of that flow chart, it has me test the voltage across the battery terminals while revving the engine. When it was revved to 2500 rpm, it was considered good if it was above 13.5 V. Mine was sitting right at 13.5, but it was hard to keep the rpms right around 2500 rpm. At 5000 rpm, it was supposed to be less than 14.8 V, and mine was at 14.2 V. So, I could have reasonably assumed that the charging system was good just by that if I hadn't gone on to the later tests on the stator. I guess my question is, is it possible that my tach is inaccurate? It is 25 years old, so I wouldn't be surprised, though I don't know how those things go. I assume it was never intended to be super accurate and rather just a guide.

Anyhow, I'm going to now check into getting the stator coils rewound or just buying a new one. Then I'll run through the tests again once it's fixed.

Thanks!

Branton

crazypj said

generator puts out max output for extended period and fries regulator.

and

New battery fitted which goes flat due to discharging through stator windings

Do you have a bike with two seperate charging systems? Generator (dynamo) and a stator (alternator)

I have one Harley putting out way too much (about 8 or 9V) and frying batteries, probably a sticking regulator (actually I know this) My solution replace battery, generator,coil,condenser, and lights with 12V and get rid of many other electrical problems at the same time.

My charging system (as far as I know) consists of a rotor on the crankshaft, surrounded by a stator, which sends the current to a voltage regulator/rectifier and then the battery. I'm not sure what you mean by having a generator as well.

Alternators and generators are two different types of current-generating device.

Both have stators, which just means the stationary part. Both also have rotors - the rotating part. What the stator *is* on both is different.