Hi,

A repeat of a story from a while back.  Got stranded in town last week with a flat bettery and had to call for a jump start.  So here is what I have doen to test things:

1.  Checked the stator output and the AC voltage rises with rpm nicely

2.  Did the static tests on the Regulator and it 'appears' fine.

3.  Battery has been recharged okay and starts the bike. 

I modded my logging system to record battery voltage and the voltage NEVER goes above 12.60volts ish.....I am not seeing the expected 13-14 volts accross the battery terminals when RPM increases.

Could a battery on its way out hold the voltage down this low?

So is this a symptom of the battery being buggered or the regulator acting up?

Logging of startup...once crusing, the voltage does not rise above 12.6 volts.

What was the AC voltage ? look for around 35v at 2000 rpm
Unlikely to be a battery problem.
Did you measure any resistance from the unplugged stator to ground ?
Checked the regulator grounding ?
If everything checks, probably the Reg'

cheers....damn. I forgot to check the stator resistance when I did the tests - I'll do it this morning before I head to work.

1.  Voltage went to about 50-60 volts when I reved the engine (but I cannot tell what rpm I was doing to get that reading)

2.  I followed a proceedure I downloaded from the Internet on checking the Regulator and everything looked good.

• Fwd/Reverse Bias Test/Diode Test: This check is testing the Diode function to ensure it is regulating the AC current for the stator into DC Current.
• Switch multi meter to Diode Scale.
• Place your Multi meter positive lead on each AC output wire.
• Place your multi meter negative lead on the battery Charge wire.
• The meter should read voltage typically around .5 volts.
• Next, switch your multi meter leads putting the negative lead on the AC output wires and the Positive lead on the Battery Charge Wire.
• The reading should be Infinite.
• With your meter on the same setting, place your multi meter positive lead on the regulator ground wire or to the regulator directly, and then place your meter negative lead on the AC output leads.
• The meter should read voltage typically around .5 volts.
• Next, switch your multi meter leads putting the negative lead on the regulator ground and the Positive lead on the AC output wires.
• The reading should be Infinite.

Okay...well this is just plain wierd!

1. I have AC voltage from the Stator that increases with RPM
2. I have 0.4 - 0.5 ohm resistance accross the stator which is about right for an old Evo system
3. BUT I also have 0.5 ohms to the chassis for each of the stator pins - so its shorting to earth.

How the hell can the unit pass 1 & 2 above and be shorted to earth at the same time?

Did you measure the stator resistance with the regulator disconnected?

Yes...I unplugged it and poked the tester leads into the terminal holes.

yes....Its an old Evo (1986) and the Stator output is two wires.

I think kiwidave may have provided both your explanation and solution to your problem.

Cheers...I'm ordering a new one today from Harley Heaven (@$78 its not a bad deal - unless someone has a better price they know of)

Cancel that Harley Heaven order - the price went from $78 => $150 in 24hours... Griffin have Drag Specs ones for $65 so am looking at them.

I also tested the stator output last night by poking two pins through the cable from the Stator to the regulator and measuring the AC voltage output under RPM - it got as high as 12.6volts so its definitely my stator.

Pretty irrelevant, as anyone who has the test equipment should know how to use it.
Most (if not all) PAT inspection gear these days have a 250v,500v and 1000v setting
The 250v setting is required for testing equipment with surge arrestors etc', and is more than safe.

lol...I remember those things...we called them "Meggers" and they would really pack a punch once you spun them up. We used them to test aerial coax installs.

I remember a bloke who I used to work with would give himself a "jump start" with the megger to make sure the batteries had enough oomph for the job. He didn't like using the "battery check" function....

Update: Okay so I pulled the primary apart and removed the stator and sure enough its a dead short from the output pins to the steel body; I'm not too fussed as its lasted nearly 20 years and was sitting behind the turbo so I think that the heat may have gotten to it in the end (will look at a heat shield this week). Rang our fine Sponsor Rollies and ordered a new one on the spot, should be here soon.

Mind you the stator is only the tip of the iceberg....
- Found the oil filter mount had come loose and the whole unit was just hanging by the hoses, so just as well I parked her up to do the stator as that job meant I had to remove the starter motor anyway.
- Primary housing bearing race has walked out and buggered the inner seal - I must admit I was expecting this as she was leaking bad.
- Transmission Sprocket was LOOSE on the shaft; darn bolt must have backed off somehow. (thank goodness that small allen cap screw held the bolt in place)
- This must have buggered the Transmission oil seal as its weeping now as well - just as well I have a spare
- Front and Back cylinder base gaskets look to have been weeping a little bit - i'll live with that for now and address when I put on the racing heads in 6 months time.

So much for going for a blat this weekend.....sigh

I rest my case, speedzter.

I don't know WTF your on about lurker, but i think you need the rest

i second that. have a long fukin rest lurker