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Motorcycle Discussions => British Bikes => Topic started by: tony fry on July 14, 2016, 07:33:00 PM

Title: triumph 21 wiring
Post by: tony fry on July 14, 2016, 07:33:00 PM

 can anyone help with wiring on my 21 it has been converted to 12 volts I want to fit a solid state reg/rec  witch sounds easy to fit the problem I have is2 wire alternator and 3 wires coming out of loom to go to alternator dark green light green yellow/green  any help would be nice

Title: Re: triumph 21 wiring
Post by: iansoady on July 16, 2016, 10:39:11 AM

If you still have 3 wires coming out of the loom it suggests the 12 volt conversion hasn't been done properly. The 3 wire system switched 2 of the alternator coils into circuit when the lights are switched on.

The 12 volt system is much simpler - 2 wires from the alternator to the reg/rec then 2 wires out - one to the battery, the other to earth. It looks as though you'll have to investigate a little further.

If you have a 3 wire alternator you common the light green and dark green then use this as one input to the reg / rec, the other being the white.

Title: Re: triumph 21 wiring
Post by: tony fry on July 16, 2016, 06:03:54 PM

thanks very mutch I will give this ago

Title: Re: triumph 21 wiring
Post by: tony fry on July 17, 2016, 07:30:50 PM

I have done this meter on battery says charging but amp meter on discharge any suggestions  would be welcome       

Title: Re: triumph 21 wiring
Post by: Rex on July 17, 2016, 09:16:36 PM

Reverse the ammeter connections?

Title: Re: triumph 21 wiring
Post by: chaterlea25 on July 17, 2016, 10:56:13 PM

Hi,

Quote

2 wires from the alternator to the reg/rec then 2 wires out - one to the battery, the other to earth. It looks as though you'll have to investigate a little further.

Quote

I have done this meter on battery says charging but amp meter on discharge

If you wire as suggested the charge does not go to the ammeter but straight to the battery
The wire you put to the battery needs to go to the ammeter via the (brown/blue? I think?) wire
the one that was connected to the old rectifier , this will have battery voltage on it

John

Title: Re: triumph 21 wiring
Post by: iansoady on July 18, 2016, 11:28:09 AM

Yes, I had omitted the ammeter in my brief description.

The trouble with old wiring is that you never know what bodges have been carried out in the dim & distant. I must confess to having perpetrated some myself......

Title: Re: triumph 21 wiring
Post by: tony fry on July 18, 2016, 07:33:42 PM

ok thanks I will try this