lack of charge when headlights on

Information relating to the Matchless G2 or AJS Model 14 250cc Lightweight
Locked
robot
Deceased
Posts: 75
Joined: Mon Jan 01, 1990 12:00 am
Location: BEDFORDSHIRE UK

lack of charge when headlights on

Post by robot »

'Mornin' all
In spite of an alternator re-build (FTW, Sheffield), a complete re-wire and a new ammeter, I cannot get a charge reading when the headlight is on on my 1962 Model 14 AJS. Battery is fully charged, I get 8 volts at the solid state rectifier, a couple of amps + with pilot light on but a hefty 4-7 amps with the headlight on and minimal improvement of a couple of amps when the 'bike is revved.
It's driving me potty - that's an appropriate expression for an AJS problem!
I've had the laternator back to FTW and all is OK. Is there a link missing in the lighting switch? That's all I can think of.
Robot
wilko
Posts: 2337
Joined: Wed Oct 12, 2005 10:45 pm
Location: victoria AUSTRALIA

lack of charge when headlights on

Post by wilko »

well robot, it looks like yout extra coils aren't being dialled in by the switch, if its the original wiring setup? douglas
robot
Deceased
Posts: 75
Joined: Mon Jan 01, 1990 12:00 am
Location: BEDFORDSHIRE UK

lack of charge when headlights on

Post by robot »

Thanks, Douglas
So presumably, there is a link missing in the lighting switch?
Agreed?
Robot
User avatar
Tolly
Member
Posts: 647
Joined: Mon Jan 01, 2001 12:00 am
Location: KENT UK

lack of charge when headlights on

Post by Tolly »

Yes, when you put the light switch in the headlight position it effectively links two of the alternator wires together to use all coils on the alternator. Have a look at your wiring diagram. By the way, are you still 6 volt?
_______________________________________________________

Experience is something you don't get until just after you need it.
Don Madden
Member
Posts: 2882
Joined: Mon Jan 01, 1990 12:00 am
Location: USA USA

lack of charge when headlights on

Post by Don Madden »

As Tolly says, when the lights are switched on the second, higher output, set of coils is switched into the rectifier.

The current passes through several connections & the switch, of course, so many places to have a poor connection.

Clean & check all of these. Clean & lubricate the switch contacts as they corrode some & collect dirt.

I am more familiar with the Lucas switches than the Wipac used on lightweigts but the former will last for many decades as the contacts are brass & only form a light patina with age.

Converting to 12 volt eliminates switching of the coils, simpifying the circuit as well as being more efficient.

Cheers, Don.
robot
Deceased
Posts: 75
Joined: Mon Jan 01, 1990 12:00 am
Location: BEDFORDSHIRE UK

lack of charge when headlights on

Post by robot »

Thanks, chaps. I'll have a go this coming weekend and report back. I should say that the new wiring harness complete with switches is via Colin Farrington but FTW did say that he's experienced trouble with the pattern lighting switches, made in China (where else for God's sake!)
Robot
Don Madden
Member
Posts: 2882
Joined: Mon Jan 01, 1990 12:00 am
Location: USA USA

lack of charge when headlights on

Post by Don Madden »

Many of the replacement electricals are made in India, too where labor costs are low. But without these sources, we would not have affordable alternatives.

It seems that the Hinkley Bonnevilles destined to the Western Hemisphere are now being assembled in Thailand. There are reports of some problems, but when the first ones came out of the UK factory there were problems, too, as one would expect of a new model.

It is truely a global economy & I expect to have to adjust.
wilko
Posts: 2337
Joined: Wed Oct 12, 2005 10:45 pm
Location: victoria AUSTRALIA

lack of charge when headlights on

Post by wilko »

i'm with you don!! the switches and ammeters from india are actually superior to lucas versions they are well made if you have aclose look, and the ammeter is steady as a rock. but of course there will be different quality manufacturers there as well. douglas
robot
Deceased
Posts: 75
Joined: Mon Jan 01, 1990 12:00 am
Location: BEDFORDSHIRE UK

lack of charge when headlights on

Post by robot »

Thanks. I've contacted A Osbourne who has given me useful tests.
Robot
Locked