Huntmaster keeps blowing fuses - Help

[david weare]

Dear Forum

1955 Huntmaster - running 6V positive earth

The lighting circuit - I have a 10A blade fuse

Now every time I put the headlamp on it blows.
I've been round the bike, disconnecting this & that and testing - still blows

Blows even when the bike is not running so presuming not a overcharging / dynamo issue

Checked for any wiring touching frame -

Is there a classic culprit for this?
Wondering whether it's the 3 position light switch on the headlamp?

Anyway -- I'm out of ideas & any suggestions gratefully received

P.S. Does anyone know where to buy 6V headlight bulbs on a Saturday in the UK in 2023?

Best

David

[will_curry]

From what you say, I'm sure the fault lies in the wiring from the light switch in the
headlamp to the dipswitch and from the dipswitch back to the headlamp bulb.

I'd check the dipswitch first. I've known the wiring underneath to touch the
handlebar and I've also known the internal mechanism to jam across the
contacts and so connect both filaments of the bulb to the battery.