Regulator/ Rectifier question

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MoriniMike
Posts: 19
Joined: 08 Mar 2011 17:42
Location: Copenhagen, Denmark

Regulator/ Rectifier question

Post by MoriniMike »

I have a 78. Sport with 2 yellow, 1 green and 1white. Alternator. I’m trying to work out wich regulator is correct for this alternator. I have a red one and a black one.
I’m not getting any power to the battery. What regulators fit what bikes?
Morini047
Posts: 22
Joined: 07 Nov 2020 10:22
Location: Karlovac, Croatia

Re: Regulator/ Rectifier question

Post by Morini047 »

Red is 6V. but this is not a reliable method of identification by color.

If you have problems with the regulator the replacement for the original is from a lombardini tractor https://www.ebay.com/itm/392945776435
Steve Brown
Posts: 1390
Joined: 12 Nov 2007 23:44
Location: Leicestershire

Re: Regulator/ Rectifier question

Post by Steve Brown »

That's the simplest type of rec/reg. If you need a replacement then any common rectifier for a 2 wire AC input that can handle 120Watts or more should do. Your type of alternator puts out around 90Watts. Not sure about the colours you mention but 6 volt is not relevant here. Most of the original supplied rec/regs have markings on the connectors like- G, G, B, M, R. G=giallio/yellow, B=Bianco/white, R=Rosso/red and M=Marronne/brown.
Yellows are the AC from the alternator.
White is an earth from the stator plate (a sort of belt and braces extra)
Brown is a switched live 12 volts.
Red is permanent live 12 volts Best via a fuse.
Some alternators don't have the red lead.
Please excuse me for any mis spelling of the Italian or the English.
There are some good explanations on the Dutch club website and there is a link to it from this website.
It's worth testing the output from your alternator before you condemn the rec/reg too.
Mark from Berkshire will be along soon to correct any errors in this. :wink:
All donations to the rest home for old Camels, Leicestershire.
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