Left hand mirror hole 1968 R50US

[Huppmar]

Does anyone know the thread size for the hole where the mirror goes on the clutch side on a ‘68 R50 US? I received an Albert mirror and the website says the mirror’s thread is 8mm. I found the mirror isn’t large enough for the existing hole on the clutch side of my bike so I’m guessing the hole is 10mm…? Thought I’d ask first before going to Ace and trying different bolts. Thanks.

[schrader7032]

Welcome to the forum! I'm not using that hole on my '69 R69S so I measured the ID of the threaded hole...it's about 7.5mm. Looks like the threads are more like fine threads. Oh, and they reverse thread!! I think that means left-handed.

[Tinkertimejeff]

Is there a chance you have a /5 clutch lever mount? That would explain the size difference. You can get a thread repair kit for that left hand mirror threads also.