Lucas headlight switch

[Guy Wilson]

Does anyone have any experience with either servicing  these switches (if they are serviceable) or know why they stop switching? The switch will move though all three positions if the round contact on the reverse side of the switch is helped by putting slight pressure on the contact. it will move over the static contacts..without assistance, it won't budge..  Is it the round contact thats worn thats stoping the contact riding over the static contacts or the housing the spring is mounted in .. It looks like out would dismantle, but be hell to reassemble... again any advice appreciated!  I have ordered a replacement, but I would much prefer the original patinated one,
Many thanks
Guy

[groily]

Your enemy here is corrosion Guy, especially on three of the four most important terminals (ones you actually need). The threads in the female bits are almost certainly pretty horrible even if you can get the screws out. Good electrical contacts may be hard to regain, reliably.
Although I'm a big fan of patina, in this case I think i'd be happy to use a replica because I think function is going to be hard to maintain, even if 'form' isn't soemthing to trouble us! The bakelite isn't too pretty either round the edges. Probably doesn't rain much where you are (or if it does it POURS!) but  I think that's a part for the 'How Things Were' shelf.
(If you weren't in Africa and I in France, you could have a better original one from the box of bits sitting here very gladly.)

[Rex]

Be careful with the modern repro's though.
I've had two where the knob has to be turned hard right to even light the headlight, and even then a bump will see it turn off again. Cheap construction again, I suppose.

[Billybream]

Second your comments Rex, my repro switch has a mind of its own

[jhg1958]

Not sure where you have ordered yours from but my replacement switch is first class. I can look it up if it helps. My 1966 Triumph had lighting switch problems and I changed that me too.

Many things on these bikes need replacing. I am never worried if it is not an exact replacement as long as it looks right.

My next thing to replace are the handlebar levers. The hole is worn oval and will never be right unless I find a kind engineer to drill and fit bushes.


ignore the pedants.



John

[Guy Wilson]

thanks all! I have a replacement coming from Feked in the UK.. the picture is deceiving though.. Its coated in grease and is not corroded at least on the terminals.. all the screws move happily.. the issue is the small roller thats on the end of spring from the central switch that rotates.. the roller won't jump the connectors unless I put a little pressure on the spring to reduce the tensions..
I seem to remember dismantling a previous switch and couldn't get it back together.. if there is nothing to loose, I may do the same with one to see why there is so much resistance in the centre mechanism..
Guy

[Rex]

Feked? Best of luck then...

[Guy Wilson]

not your recommendation? have you had bad experiences?

[muskrat]

not your recommendation? have you had bad experiences?

LOL, replace the "e" with "uc". Just my experience.
Cheers

[Swarfcut]

 The real problem with a lot of this repro stuff is that the quality is sometimes not what you'd like. The actual manufacturing source is likely to be the same from which ever local supplier you use.

  The way suppliers deal with the inevitable problems varies from almost red carpet treatment to "Thanks for the money, now go forth and multiply" so to speak. These  latter outfits are mentioned somewhat frequently on this very Forum.....

 As for that failed switch, the design life was a few short years, so it has done well to last this long. With patience and skill it could be restored, but for now a repro is worth a punt.

 Swarfy

[Guy Wilson]

yes,  agreed.. they were not intended to last 60+ years... I appreciate the input though!
Guy

[Guy Wilson]

so, I dismantled it completely, cleaned and greased the various parts and its switching perfectly now... success!
It has four positions though... off , + 3 more, 2 and 3 would be side and head light.. whats the first position for? could the off position be for the magneto cut off and position 1 be for magneto on?  just curious..
Guy

[Swarfcut]

 These switches always seem to have more contacts than we need on the relatively simple BSA Wiring Loom.

 BSA Service Sheet 808 shows wiring diagrams for A,B,C,&M ranges, some more complex than others, so take your choice, they all do the job.

 Before now I've used a simple toggle switch and handlebar dip switch to wire up the lights well enough to pass our MOT, originality is fine, but can be a pain sometimes.

 Swarfy

[jhg1958]

When I bought my switch I was determined to understand how and why it works especially as I made a custom wiring loom.

There only three switch positions and 7 contacts plus common.

When the switch is off it connects
position 4 (Pilot light) and 5 (tail and speedometer light)
I do not know why as this does nothing
and Position 7 (not used) to common (not used)

When it is the middle position it connects
Position 3 (from ammeter) and 4 (pilot light) and 5 (tail and speedometer light)
So powering the lights except the headlights

When in the Right hand position it connects
position 3  (from ammeter) and 2 (headlamp)
Putting on the headlamp dip and and full via the dip switch
it also connect
Position 2 (headlamp) and 4 (pilot light) and 5 (tail and speedometer light)
so maintaining the other lights.
it also connects
position 1 (not used) to common (not used)

Crazy I know

John

[trevinoz]

Guy,
Is there a letter designating the fourth position?