Any ideas what this 4 - position Lucas switch fits ? Letters state "Off, C, H, L".........??? (and no, it's NOT James ML !!! That switch states "Off, T, H, L" and doesn't bear the "Lucas" name !!!)

email (option): sjmwdbikemad@aol.co.uk

I was always given to understand it stood for Convoy, in that in the C postition only the rear lamp was lit.

then again it could be one of those myths...

Normal switches show this as "T" (tail only) for convoy and this is an original Lucas item...........I'm thinking "C" for "Charge" ("CH" found on Miller switches)...........it's stuck into a khaki-green headlight panel at present...........haven't a clue what bike or model this may have been for.........????

email (option): sjmwdbikemad@aol.co.uk

Found it !!!! Thanks to Rob VDB's site by the way.......

Pre-war Norton 16H (1936) it seems........"half-charge" switch..........

Is this rare then....?

email (option): sjmwdbikemad@aol.co.uk

Not just Norton...All machines fitted with a 3 brush dynamo I think...

About the same degree of rarity as a WD switch I would say...I've come across them now and again....Ian

email (option): ian@wright52.plus.com

Steve,
The small rivits on your last picture are for an alloy mounting that the half charge resistor sat on. Pre 1936 Lucas motorcycle dynamos were 3 brush types with a cut out mounted in the end of the dynamo. these systems ran without a voltage regulator MCR1. The switch position is OFF all lights and no charge, Charge position is charging through the half charge resistor. The other 2 positions allowed the dynamo to give its maxium charge also with the lights on.
The idea of the half charge resistor is so you can run the bike with the switch in the C position and it will not boil the battery as the charge is reduced as it passed through the resistor ( just a coil of open wire) If you thought the battery was fully charged you switched to the OFF position.
I have run my 1935 16H with the 3 brush system for the last 10 years and find it hammers the hell out of batterys, so this winter i have converted the original 3 brush dynamo to a 2 brush and disconnected the half charge resistor. I have fitted a modern solid state regulator into the toolbox, this way it all looks original. Have not had the chance to try it out yet but in the next few weeks i will test it.

Tim W

email (option): t.j.walker@btinternet.com

Hi Tim...The converted dynamos run fine...Ian

email (option): ian@wright52.plus.com

One just sold on eBay for £37.66 item number 121299686887

email (option): horror@blueyonder.co.uk

Tim/Ian/Horror - thanks for all your advice !

email (option): sjmwdbikemad@aol.co.uk

Ian Wright

Hi Tim...The converted dynamos run fine...Ian

email (option): t.j.walker@btinternet.com

Dave,

I know, I bought it and thought it was not too expensive actually. And as stated above it does indeed fit in a 3 brush dynamo system. The 3 brush set up is rubbish do conversion is highly recommended. All my prewar bike with instrument panel in th headlamp should have it together with the panel with the aloy piece inside.

Regards,
Leon

email (option): leonhop3@planet.nl

Well done Leon, I was watching it but didn't have a use for it right now. I buy too many things "just in case" when I don't really need them

email (option): horror@blueyonder.co.uk

Hello Steve and others

I also have an inside view of the instrument panel with 4 position half charge switch on the website showing the resistor and ammeter as well.

Have a look at http://www.wdnorton.nl/Electrical_equipment_page/1936 headlamp panel half charge resistor and switch.JPG

Cheers,

Rob

email (option): wd16h@telfort.nl