Most prewar British motorcycles used 1" (25,4mm) diameter handlebars. All Vincents have these and many Nortons pre 1955.
Triumph used their own system: 1" on the left and 15/16" on the twist grip side. Around 1960 this changed to 7/8" like everybody else.
BREXIT. After 1-1-2021 no more shipping to the UK.
Customs and new VAT rules make this impossible.
You were nice customers, Sorry.
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