ES2 Featherbed petrol tap

Many moons ago, I had a similar problem with my Dommie, albeit with an ali tank. At my local builder's merchant, I purchased a short chrome extension piece, 1/4" BSP male/female. This dropped the tap lower by  an inch or so, and below the level of the frame tube. Problem solved.

A push pull HexagOn tap might not fit but a lever tap (BAP type or similar) fits mine.  I take care which way it faces so it doesn't get turned if I lift the tank on and off.

Spherical valves meant for LPG and various industrial applications flow well, don't leak and last a long time. Also are cheap.

They don't look like British bike parts and don't have a reserve, if that matters to you.

Hi,
I did as per Michael's suggestion (quite independently) back in 2020 when resurrecting my 650 during lockdown.
See Roadholder #395.
I used a 'BAP' type tap as sold by Hitchcocks, the Enfield people.
Everything is still there and working as intended 5 years later.
Regards,  George 

On one of my Italian bikes I became so frustrated with the offerings from italy that i re-threaded the tank to BSP and fitted a BAP lever tap .  My Dommy uses an orriginal Ewarts  though . I have spare parts and have learnt how to successfully re-furbish them.