I have just relocated my turn signals (front ) after removing the hardwere from the handlebars i now need to fit a new nut to my r/h mirror stem , does anyone know the stem thread size ? cheers

 

What did you do with the old nut? You might be SOL being in the UK, I think the Harley fittings are SAE not Metric. But I've been known to be wrong.
Ala I believe they're 1/4x28

 

hi i still have it but its not a great looking thing seeing as it was part of the turn signal mount !

 

Not sure what you have there in the way of a large hardware store. Take the nut in and find a bolt that fits it. Then you can find a new stainless nut that fits that bolt. Put it in your pocket and leave. Or pay for it. LOL