alternator 6 or 12 volt

chrisf1

Joined
Aug 23, 2015
Messages
188
Country flag
Hi again everyone yet another problem how can I tell if the alternator on my bike which at the moment is in pieces is 6 or 12 volt I have it off and in my hand but cannot see any I.D. or numbers anywhere and there are no bulbs in the bike to help me in that way the battery was replaced with a 12 volt by the last owner who only had it for resale and he put a 12 volt on but as I am rebuilding I need to be sure many thanks Chris
 
How many stator wires?
What are the wire colours?
Open or encapsulated coils?
How many laminated cores inside (6 or 9) ?
What make/type is the regulator (or regulator/rectifier)?
Is there a Zener diode?

Photos?
 
Hi LAB and thanks for your reply I am attempting to post 3 pics showing both sides and the 3 wires of which 2 are green and cream and the 3rd is either solid green or green and black and hopefully you will be able to tell me what it is many thanks again Chris
alternator 6 or 12 volt


alternator 6 or 12 volt


alternator 6 or 12 volt
 
Hi again yet another item that I believe is the rectifier please confirm still got a lot to learn thanks Chris

alternator 6 or 12 volt
 
chrisf1 said:
I am attempting to post 3 pics showing both sides and the 3 wires of which 2 are green and cream and the 3rd is either solid green or green and black and hopefully you will be able to tell me what it is many thanks again Chris
Click to expand...

An extremely ancient 3-wire, single phase RM?? stator-that's what it is. :)

Those "green and cream" wires are in fact green/yellow, and green/white! The other being a green/black.

If the green/yellow and green/white wires are connected together ahead of the rectifier then it should operate as a 12V stator.

Information on how to use it as a 6V stator can be given, if necessary.

(Awaiting correct rectifier photo)
 
If you mean this item in your Photobucket album, then yes it is the normal positive earth Lucas rectifier.

alternator 6 or 12 volt


Is there a Zener diode (regulator)?
alternator 6 or 12 volt
 
Hi again I cannot see a zener diode what does it connect to and I will try again thanks I do not know if it makes any difference but at the moment it is running a distributor and coil which I intend to change for electronic ignition if possible without needing to use a battery is it possible because deciding where to put the battery is a problem, don't know how the pic went wrong but I am no techy but can get by with a spanner many thanks again Chris
 
chrisf1 said:
I cannot see a zener diode what does it connect to
Click to expand...

If it's there, it should be connected 'somewhere' on the negative side of the battery (for positive earth) and is usually mounted either on an alloy heat-sink plate or some other substantial metal component that will dissipate heat?
 
I think I have found it quite a bit bigger than the one shown mounted behind the headlight
alternator 6 or 12 volt
 
Yes, that's it.
The circular plate is just the heat-sink.
 
Great how do I set this up to run without a battery and electronic ignition thanks Chris
 
chrisf1 said:
Great how do I set this up to run without a battery and electronic ignition
Click to expand...

I take it you meant without a battery but with electronic ignition?

For a points system this would involve fitting either a 2MC or similar type capacitor or replacing the regulator and Zener with a reg/rec unit containing a built-in capacitor such as the Boyer Powerbox or Podtronics Pod-4-1 Max.



Attempting to run electronic ignition could be another matter entirely and whether it worked at all (considering the ancient alternator) is likely to depend on the particular electronic ignition system.
 
You got it right that's exactly what I meant and thanks for all your help, when I can afford all I have to get I will no doubt need more advice fitting it but now we have a plan thanks very much Chris
 
Hi Triton the budget includes a lot more than alternator and battery if I can fit it, would prefer not though Chris
 
The unencapsulated stators, like the one shown here are fairly unreliable. The one on my 650ss fell apart in the middle of an ACU National Rally in the mid 70s. The coils become loose and the connections fall apart. It's why they (Lucas) went to encapsulated alternators fairly quickly. Thank God for magnetos!!
For my money, replacing the alternator would be towards the top of the New Bits Required list.
cheers
wakeup
 
Hi again I am about to order my new alternator and it is an encapsulated RM 21 please bear in mind I intend running one of these Boyer Bransden capacitor power packs eventually to do away with the battery should I go for one with more power output or should this be sufficient, also I have seen that the rotors differ in size mine is 70mm diameter was this changed when they moved to encapsulated alternators or are they the same size ? many thanks Chris
 
chrisf1 said:
also I have seen that the rotors differ in size mine is 70mm diameter was this changed when they moved to encapsulated alternators or are they the same size ?
Click to expand...

The rotor for the encapsulated (and late unencapsulated) stators is 2.7/8" (72mm) diameter, so yours is probably correct, however, if the rotor is anywhere near as old as the stator then it's likely to have lost some of its magnetism by now which will reduce output.
 
I have no idea how to measure magnetism but it is pretty strong I keep it in a sealed bag as everything sticks to it and does not come off easily should I replace to be safe cheers Chris
 
chrisf1 said:
I have no idea how to measure magnetism
Click to expand...

If the rotor will cling to a screwdriver blade without falling off when lifted from the bench, then it's probably OK (check each magnet), but it may still not be as good as a new one.
 
You must log in or register to reply here.
Back
Top