This NOS twist grip has had a modification that reduces it from 1" down to 7/8",it looks like a professional job as could be done in army work shops ,never seen one like it before and being never fitted/used makes it possible an army work shop modification to use up 1" twist grips from stock .

Not seen that before Steve!

Could it have anything to do with the bikes that had 2 diameter bars? like Ariel and Triumph, then it would work, and fit those.

Lex

email (option): welbike@outlook.com