Just checked my existing and it measures 295mm long with 16mm diameter
Does that sound right?
13mm would mean that I could not clamp the indicators tight
Hi , i can shed some light on this . The bike when i bought it had no rear indicators so i found a piece of tube and cobbled it up . This was long before i even heard of the internet and computers .The indicators should have a rubber damper in the end of the stem the ones i picked up may be never had them hence the larger dia tube .I think i used a mini metro front slam panel bracing tube .