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Hey folks. I'll keep it brief just now so I can get some testing done and get back with some results.

I seem to have twisted my brain in knots trying to figure out what the issue is here. I'm not getting 14 volts at the battery with the bike running.

Battery is fully charged. (I'm very familiar with batteries and charging so no need to go there).

The wiki on the forum (Diagnosing Charging System Problems) doesn't match the wire colours on the bike. Can some kind person have a quick look at the attached diagram and see which wires I should test.

many, many, many thanks in advance!

p.s. With bike running I am getting >25v AC out of the Yellow ( 8 ) and Grey/Blue (2) wires. Only getting about 3v from blue wire and about 1.5v at lights. This is the same with the bike started with battery connected or not.
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Can you be more specific about the voltages please, mentioning whether AC or DC for each?

If you're only getting 1.5V AC at pin 1 for the headlight etc, then your regulator has given up its smoke (it should be 12-14V AC) - likewise if you've only got 3V DC out of pin 8.
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Ha! I was just about to post that

I was just wondering if I should check if the lights were AC or DC. Behold - 12v AC!! I've clearly a lot to learn about bike electrics!!

I couldn't figure out why they were so bright with such low 'DC' voltage

Pin 8 and Pin 2 are >25v AC

The 3v is from the blue wire that comes from the stator going to the battery via the key switch
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At what RPM are you getting the 25VAC on Pin 8and 2? Let us know what it is at 4000rpm.
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Quite low rpm - no rev counter so don't know exactly...

I don't really understand the charging circuit. Why is there a 12v supply going to the stator. It must be going in that direction as there's no diode in place to stop it?
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The blue wire should show 12-14V DC - it's meant to be connected directly to the battery via the 7.5A fuse. If it's disconnected then you'll get all sorts of funny readings, the regulator needs to have that feed via the stator to pin 8.
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Everything is connected. The bike has sat for years - only has 2000kms on the clock!

The blue wire shows continuity through the coil to pin 8 and back to the battery with the fuse in place.
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Can we have a poll on who thinks the 'good' regulator is actually as bad as the first one? Laughing emoticon
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Still trying to figure out what's good or bad.

When running with no battery the 'dashboard' lights are all flickering. The fuel and oil lights come on with the brake lever.

All in all I'm totally confused about what I should be testing - the stator or the regulator.

Don't know the probability of two regulators showing exactly the same symptoms?
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oh well - just ordered another regulator. Hope that's no a waste of time and money...
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shuggy33 wrote:
Still trying to figure out what's good or bad.

When running with no battery the 'dashboard' lights are all flickering. The fuel and oil lights come on with the brake lever.

All in all I'm totally confused about what I should be testing - the stator or the regulator.

Don't know the probability of two regulators showing exactly the same symptoms?
If you run with no battery you *will* blow your headlight bulb - there will be no regulation of the high currents and voltages available on the AC side.

You may also destroy the turn signal pulse generator in the regulator - but that's unimportant if you're getting a new regulator, which is probably the duff part anyway.
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Thanks again for the reply. It's all new to me but keen to learn. I'm coming from cars where there's always plenty of power on tap form a huge alternator - not a tiny stator.



SO even a dead(ish) battery is better than no battery?

Out of interest - does the battery charge at idle or is the recharge circuit not up to it? I guess it's not if it's maxing out at 1-2amps. The 12w brake light will eat that if sitting at idle with brake on.
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shuggy33 wrote:
SO even a dead(ish) battery is better than no battery?
Yes.
Quote:
Out of interest - does the battery charge at idle or is the recharge circuit not up to it? I guess it's not if it's maxing out at 1-2amps. The 12w brake light will eat that if sitting at idle with brake on.
Very little (if any) charge gets into the battery at idle on these engines, even with no extra load such as the brake light. So if your voltage measurements were at idle, that might account for not seeing any battery charging. You need to run the engine fast enough that the headlight brightens up from its normal dimness at idle.
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This does go some way to explaining the issues.

I've been revving the engine while holding the front brake - in case it came off the stand at full revs.

There goes almost 2 amps (and associated voltage) right away. Battery is on charge so will try it later without brake on. I'm a bit less despondent now... Laughing emoticon
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