Vintage BMW Motorcycle Owners

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.

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.

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.

It’s common for the Left hand threaded holes to be tapped to a variety of sizes over the years to fit non stock mirrors or what not. My common repair is to purchase some 7/16” left hand all thread and feeding it into a Collette on the lathe where it can center drilled and tapped for M8x1.25 left hand, parted off at 10mm length. These little repair parts can be used to repair stripped handlebar controls after tapping the handle bar control to 7/16” left hand.