Rectifier or alternator ?

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Re r/r; remove it and take it to an Auto electrian, or your nearest m/cycle shop if he/ she has the ability to run the R/R tests.that should confirm if you have a duff one.
 

Kjell

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This is true. And the typical failures are the stator wires either at the stator itself or at the connections to the rectifier/regulator, or the R/R being defective or not connected to the battery. It's actually quite simple to troubleshoot.

Do yourself a favor while you're waiting for your meter and open the primary to take a look at the stator wires. They often break where they exit the epoxy stator. Then follow those wires to where they connect to your regulator. Depending on the location of the r/r there's often extension wires and associated connectors leading from the alternator.
Managed to source an analogue meter this morning unfortunately after I ordered another one from UK. So soon I will be the lucky owner of 2.
In a couple of hours I should be able to find if the bike is charging properly or not. The R/R i have on the bike is an A REG ONE 12 V which I understand are pretty reliable. If it is not charging the next course of action will be to open the primary and start from there. There are indeed several extensions on the wiring from the Alternator
 
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There is a video on how to test a R/R on the Roadstercycle.com home page.
 

Kjell

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Confirmed. The bike doesn't charge.
I guess I will start from the beginning. How much AC should I measure directly from the alternator before any R/R ?
 

maylar

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Not charging means no load and you'll probably see 25 vac at 3000, possibly more. The factory test is to put a high power one ohm load across it and get a minimum of 9 volts.
 

Kjell

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Alternator : Seems OK. Measured 15-28 Volts AC directly measured at the two cables going out from the primary. Varying with RPM which I think is normal.
Reconnected the two cables from alternator and checked wherever possible with an ohm meter and found the cable to show zero resistance where they were supposed to. Started the bike with no voltage increase over the battery poles when revving the bike over 3000 rpm
Then I tried to swap out the rectifier/regulator
( A REG ONE) that the bike had when I bought it with a brand new Boyer Power box.
reconnected everything as per Boyer schematics and started the bike again.
No change still same . I am puzzled to pit it mildly.

However in the process ripping up old insulating tape I actually found on Brown/Blue cable ( similar to the one going to the battery main) that were carrying 12V charge REGARDLESS of the position of the ignition switch. I.E it was live independent of the Ignition Switch position !

Any ideas out there ??
 

L.A.B.

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However in the process ripping up old insulating tape I actually found on Brown/Blue cable ( similar to the one going to the battery main) that were carrying 12V charge REGARDLESS of the position of the ignition switch. I.E it was live independent of the Ignition Switch position !
Brown/blue is the feed to the ignition switch so is 'live' regardless of the ignition switch position.
 

Kjell

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Brown/blue is the feed to the ignition switch so is 'live' regardless of the ignition switch position.
Understood. Then I am even more puzzled. This particular brown blue was taped side by side to the two wires coming out from the alternator a little bit above the primary and just cut
 

Kjell

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Understood. Then I am even more puzzled. This particular brown blue was taped side by side to the two wires coming out from the alternator a little bit above the primary and just cut
And I am having plenty of feed to the ignition switch from other Brown/Blue cables that actually goes to the ignition switch
 

L.A.B.

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Brown/blue would also have connected to the original rectifier, Zener diode, 2MC capacitor and auxiliary power socket.
 

maylar

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Brown / Blue is the color of battery wiring. Rectifier / Zener diode / capacitor originally. An extra unused one exists in the harness for the optional police version Norton with flashing lights etc. but that's under the tank.

Where does the output of the rectifier/regulator go? It should connect to one of those brown/blue wires.
 

Kjell

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Brown / Blue is the color of battery wiring. Rectifier / Zener diode / capacitor originally. An extra unused one exists in the harness for the optional police version Norton with flashing lights etc. but that's under the tank.

Where does the output of the rectifier/regulator go? It should connect to one of those brown/blue wires.
Yes it does indeed. Then I measured with ohm meter from that particular cable down to the negative terminal on the battery and It showed zero. In other words the cable that connects to the output from the regulator Black) has connection all the way to the battery. Thats whats puzzles me. AND I tried two regulators
 

maylar

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And the red wire?

If you have AC going into the regulator there should be DC coming out. Measure at the unit's wires, take nothing for granted.
 

Kjell

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And the red wire?

If you have AC going into the regulator there should be DC coming out. Measure at the unit's wires, take nothing for granted.
The red wire goes to earth ( positive side of battery) as it should do. Connection verified with ohm meter
 

Kjell

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The red wire goes to earth ( positive side of battery) as it should do. Connection verified with ohm meter
Actually what I think I will do is bypass the whole wiring system and connect the output from the regulator straight down to the battery. If it doesn't show any charge then I guess it must be low output from the alternator despite normal voltage readings without load
 
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You have done a test on the AC wires and got a result which looks ok.

The next voltage and headlight bulb test is on the regulator output DC wires. Have you done that?
 

maylar

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Are you confident that the alternator AC is making it to the rectifier?
 

Kjell

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Are you confident that the alternator AC is making it to the rectifier?
What I have done, again with an ohm meter measured the connection where the alternator wires meet the regulator and measured 0 ohms from that point down to the output wires just above the primary. The connection shows 0 ohms so it must be ok. Since I measure AC out from the alternator and the wire from there up to the rectifier is OK I concluded that there is no problem there.
 

Kjell

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You have done a test on the AC wires and got a result which looks ok.

The next voltage and headlight bulb test is on the regulator output DC wires. Have you done that?
I will use a testlamp between the output of the regulator and earth. If that one shows light something must be coming out of the regulator. If it does I will connect the output wire +12.8V negative and the other directly to earth on the battery. If it doesnt show at least 14 volts at 3000 rpm then I guess the alternator is not giving enough output under load. Does this sound about right ?
 
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