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  #11  
Old 13-06-17, 21:08
westlin westlin is offline
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Regardless of the voltage it would not explain the excess heat. Is the stator throw to much voltage again something to check
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  #12  
Old 13-06-17, 21:10
purplewesty purplewesty is offline
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Thanks Westlin.
I had an autoelectrian take a look and he was stumped ( albeit he doesn't specialise in bike engines) and he's going to take some readings from a working bike for comparison.
I've not got a Haynes manual yet ( getting one ordered) but the readings he took with his meter seemed to suggest the stator was ok.
The only changes I've made to the electrics during the rebuild was to fit a bike fuel pump instead of the usual set up seen on these cars.
All works fine though apart from the reg issue.
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  #13  
Old 13-06-17, 21:16
asklepios asklepios is offline
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So to be clear, the regulator is functioning but hot? The regulator is 'in a relationship" with generator, battery, kill switch and earth. I can not believe the fuel pump is the issue.
Check the mini circuit again, paying attention to the kill switch. They are tricky devils and I would not be surprised that there is is build up of resistance inside. You do know that if incorrectly wired or poorly earthed, the regulator gets fried. I used to know the reason for this ....but......
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  #14  
Old 13-06-17, 22:18
purplewesty purplewesty is offline
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Quote:
Originally Posted by asklepios View Post
So to be clear, the regulator is functioning but hot? The regulator is 'in a relationship" with generator, battery, kill switch and earth. I can not believe the fuel pump is the issue.
Check the mini circuit again, paying attention to the kill switch. They are tricky devils and I would not be surprised that there is is build up of resistance inside. You do know that if incorrectly wired or poorly earthed, the regulator gets fried. I used to know the reason for this ....but......
Now that could be a good call.
I noticed that when the kill switch is in the off position the terminals are a bit on the loose side.
When in the on position they are fine but the kill switch could be an issue now you mention it.
I might remove it and try run without to eliminate from the equation.
I must admit I never considered it could be a problem.
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  #15  
Old 24-12-17, 09:26
learnerdrive learnerdrive is offline
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Hi Purplewesty.
I realise this is an old thread but I'm interested in finding out if you ever solved the problem?
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  #16  
Old 24-12-17, 23:37
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T13EES T13EES is offline
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Quote:
Originally Posted by learnerdrive View Post
Hi Purplewesty.
I realise this is an old thread but I'm interested in finding out if you ever solved the problem?
The one on my Jedi K8 1000 has always run too hot to touch and has done so for the last 8 years !
I was told they are designed to run this way, hence all the fins and it being placed in the air flow..
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  #17  
Old 25-12-17, 16:18
purplewesty purplewesty is offline
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It turned out, after trying different new ones and getting all connections, especially the earth connection checked. There was nowt wrong with it !!
They do run hot so make sure they are in the airflow. Mounted mine in the side pod in the end.
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  #18  
Old 25-12-17, 16:55
paul martin paul martin is offline
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Was going to say that. Also helps to mount it on a heat sink alloy plate.
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  #19  
Old 25-12-17, 19:29
learnerdrive learnerdrive is offline
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That's good to hear that it was all ok and the hot rectifier was not a problem in the end and was functioning normally.
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  #20  
Old 26-12-17, 23:25
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T13EES T13EES is offline
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Quote:
Originally Posted by learnerdrive View Post
That's good to hear that it was all ok and the hot rectifier was not a problem in the end and was functioning normally.
Quote from a USA bikey just for your information :-

" The nature of charging systems generally offers two paths.
One creates constant voltage, and varying current.
The other works inversely to that, being constant current, varying voltage.
The 1st one has more drag but works better at low RPM.
THe last one is what we all have, a constant current system, and works
better at higher RPM and offers less electro-mechanical drag.
The trade off is the difficulty of regulating those voltage swings.
Dropping voltage makes heat. Dealing with tons of it creates engineering challenges.Heat degrades things.( think Turkey in the oven) makes them softer and more crunchy at the same time.
For electronics this makes things fail obviously.

In our three phase AC generating apparatus, theres really only 3 parts.
The Stator with its magnet rotor, and two electronic items, the rectifier and the regulator. In most all cases except one These two items are married together within centimeters of each other, and one bakes itself and the other, also .... mercilessly.
The regulators sole ( or 'soul' after it dies ) purpose in life is to keep the rectifier from sending anything over 16 volts to the battery.
It simply sleeps until the threshold is reached and clicks on.
Advanced ones have a taper as they activate. (shhh)
The rectifier is really only 6 diodes in basic form. 2 diodes per phase, creates a nice DC pulse to the battery, via the regulator. They are kind of dumb, doing a boring job of getting real hot while just slicing up sine waves into 3rds. They are intuitive as a peice of rock salt.
The regulator watches the voltage in the system,allowing anything under a maximum setting to pass straight to the battery from the rectifier.
The regulator is where theres any intelligence, or could be.
when voltage exceeeds the limit set by the regulator something interesting happens where you can also see the difference in traditional regulator rectifiers and the newer comming generation.
When the regulator senses the peak has been exceeded, it fires the gate on an SCR that simply ggrounds out one of the 3 phases comming from the stator. Brutally simple, this direct short to ground creates massive heat in the SCR. when the SCR fails, you have runaway voltage.
The SCR ( sillicon controlled rectifier ) is like a simple 3 pole relay with no moving parts. In our circuits they are gateways straight to hell... literally.
Its a path to ground and heat is the product. On cheap R/R models that only ground one set of windings of the stator, the stator gets damaged much sooner. Advanced models of R/R have an SCR on each stator winding to evenly ground out the stator, creating an even heat distribution pattern in the windings themselves. This makes a longer lasting stator.
None of this matters at all of course if you ride slow like a granny.

Regulator circuits fail too, getting a career baking (BBQ) by riding piggyback on hot rectifiers. when they fail it can go two ways.
Remember the regulator is the brains of the system.
Mode A is where the regulator fails to fire the SCR, closing the circuit.
Mode B is where the regulator holds the gate open, and fries stuff by overcharging.
I prefer mode A.

Your frame is a massive capacitor (electrolytic at that).
Connect your negative 1st, and dont spark your positive cable ot the resulting spike in voltage will pop any cheap or stock R/R.
And if it dont kill it good the 1st time, you can rest assured its been damaged.

About heat distribution.
THe rectifier diodes (6) make most of the heat, 70% at least.
But those SCRS when you are spinning the motor fast are giving quite a bit. One of my discoveries, by chance was how only 3 of the 6 diodes make any heat in certain arrangements. I wont spam or give away hard earned secrets, but there is a design coming that creates half the heat at full power load based on this data."
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