Flat battery - why?

[bakalorz]

just want to add that the connections are SPADE conncetors (not bullets) and that i tested the system on several ocassions both cold and hot - and the results were the same.

i'll try steve's idea today with using the car battery for testing and post the results

thanks guys

Two things ...

If you try Steve's test, make SURE you have GOOD connections to the jumpers and that they can't become disconnected if you bump them.

If the jumpers become disconnected while the engine is running, you are running without ANY battery in the system. In addition to the other things it does, the battery acts as a filter to smooth out the fluctuating DC supplied by the R/R.
Without the battery high voltage spikes enter the system.

There are previous threads where people have had issues occur where batteries became disconnected while the bike was running, and then had the ignitor blow.

--------------------

Also, I thought of another test you can try.
This is to try to isolate if you have an issue with one of the phases, or it is something else.
The idea is to intentionally run the bike on only two phases at a time.

Disconnect one of the yellow wires from the stator to the R/R, start the bike and see how it charges (voltage with light on, voltage with light off, both at 5000 rpm)

Now connect that one back up, and disconnect a different one. repeat the charging test.

Repeat for the third wire.

----

If all three tests provide equal results (whatever they are) then it is not a problem with one of the phases and you will need to look elsewhere than my previous suggestions.


If two of them provide one level of charging (probably worse than currently charging) (running on one bad and one good phase)
and the third is different from the other two (probably about the same as it runs on all three phases now)(cause its running on two good phases, and the bad one is the one you have disconnected)
then you have isolated the problem to being a problem with one of the phases.

[psyguy]

update

with the car battery the tests are the same - charging OK with no load, but NOT charging with the headlight-bulb connected directly to the battery terminals.

here's the summary:

i connected the new (used) RR (6 wire model) i got from duaneage but the problem remains the same:

• charging OK with no load (14.5V)
• charging NOT OK when the headlight is ON (or when i connect a 55W light bulb directly to the battery) - the voltage starts slowly dropping
• all relevant connections are NEW spade connectors
• RR connected directly to the battery
• stator puts out 85+V at 5000rpm on all three phases
• all 3 stator phases go directly to the RR
• the system has been tested with the engine just warmed up from cold as well as during a few hours of riding and the results are the same
• i also tested the system with a car battery temporarily hooked up (car engine off) to rule out a faulty motorcycle battery

so, any suggestions as to what next??

[bakalorz]

just want to add that the connections are SPADE conncetors (not bullets) and that i tested the system on several ocassions both cold and hot - and the results were the same.

i'll try steve's idea today with using the car battery for testing and post the results

thanks guys

Forgot something ...
If you do Steve's test, I would expect a car battery to have a similar type of response, but to drop significantly more slowly because it has a much higher capacity.
So just because your bike battery drops MUCH faster doesn't mean its bad.

OTOH if the car battery never drops, then the bike battery is likely the problem

[psyguy]

If you do Steve's test, I would expect a car battery to have a similar type of response, but to drop significantly more slowly because it has a much higher capacity.

yup, that's exactly what happened...

[psyguy]

thanks, will do this next...

Also, I thought of another test you can try.
This is to try to isolate if you have an issue with one of the phases, or it is something else.
The idea is to intentionally run the bike on only two phases at a time.

Disconnect one of the yellow wires from the stator to the R/R, start the bike and see how it charges (voltage with light on, voltage with light off, both at 5000 rpm)

Now connect that one back up, and disconnect a different one. repeat the charging test.

Repeat for the third wire.

[psyguy]

new info

tested with one of the three stator phases disconnected (and the headlight OFF / ON):


- OFF - ON - Disconnected phase

1. 12.8V - 12.4V - yellow
2. 13.1V - 12.6V - white/blue
3. 12.9V - 12.5V - white/green

the readings probably have a margin of error of +/- 0.1V as it was impossible to get a steady reading

[bakalorz]

tested with one of the three stator phases disconnected (and the headlight OFF / ON):


- OFF - ON - Disconnected phase

1. 12.8V - 12.4V - yellow
2. 13.1V - 12.6V - white/blue
3. 12.9V - 12.5V - white/green

the readings probably have a margin of error of +/- 0.1V as it was impossible to get a steady reading

Well, that pretty much rules out a phase gone bad.

You could try using the 10 amp dc part of your meter to measure the actual current consumption of the three 10 amp subcircuits in the fuse box
(assuming your bike is wired like many are, with a 15 amp main and then 3 10 amp subcircuit fuses)

Take out a fuse and use the meter leads to connect to each end of where the fuse went
(the bikes main fuse will still protect things if you mess up)

briefly start and run the bike, and see what the actual current used by the 3 circuits is (do one at a time)
Expected values would be around (semi-educated guesses)
8 amps ignition
~1 amp for the guages/signal fuse (with no turn signal lights on)
0 amps for the lights with lights off, 5-7 amps with lights on.

After that, I'm pretty much stumped except to say try swapping out the stator ...

[duaneage]

I'm wondering if the magnets in the rotor are weak. If the rotor is AlNiCo it COULD be a weak rotor. That would cause the stator to have capacity problems as the load increased. It's a long shot but we have tried just about everything,

If there are no accessories or lights added to the bike, and the headlight is STOCK and not some super duper high output light, then that leaves the rotor magnets as last thing.

It's happened before with older bikes, but I don't think yours has an AlNiCo rotor, After 1979 almost all rotors used Ferrite which never loses it's magnetism. AlNiCo can be degaussed by heat or a physical impact. Over time AlNiCo can be weakened by strong electrical fields (like a loudspeaker) but it's heat and impact that affects them in a charging circuit.

Just a longshot.

You might have mentioned this but please refresh our memories as to when this started to occur. what lead up to the battery going flat? Was the bike always a problem to start or did it used to charge OK?

[lucabond]

Where did you connect you sense wire from the RR ? Check the voltage at that connection with the light off then on and see if the voltage changes.
Have you tried connecting the sense wire directly the the + side of the battery to see if the battery charges with the light on ? Good luck

[psyguy]

hey, folks, this thread is getting long and people are repeating the questions already asked and replied to so i'm taking this to a new thread starting with a summary

http://www.thegsresources.com/_forum/showthread.php?p=1096090#post1096090

cheers

[Matchless]

Psyguy,
Apologies, I do not want to derail the proving process, but you seem to have a very intresting (frustating) problem here it seems.
The R/R is OK
The wiring is OK
Connections are OK
Battery is OK
Headlight is OK
Routed AC wire via headlight switch is bypassed
Stator tests for voltage shows OK, but..
Maximum current supply from stator has not been proven conclusively

If your stator is a 180W unit it should be able to supply you with at least 15 Amps. Your headlight (55 W) adding another 4-5 Amps when its on tells me you are exceeding the maximum of 15 Amps total current draw, thus pulling the current excess from the battery.

I would at this stage seriously think of pulling the stator cover and give the stator a mk1 eyeball check.

Good luck