Why the pre-1970 BMW /2 came with only one mirror (and why ours does too)
Short answer: pre-1970 BMW /2 motorcycles left the factory with one mirror, on the left clutch perch, and an M8 blind plug in the right perch. BMW never fitted a pair. The KiWAV Stan Square Rise reproduces exactly that: a single left mirror, with glass that floats on a spring the way the original did, which is why it gives slightly when pressed. Neither is a defect. Both are the original design.
Every few weeks a Stan Rise customer writes to us with one of two questions. "Where's the right-hand mirror?" Or: "The glass moves when I press it. Is it faulty?"
Both are fair questions. Both have the same answer: that's how the original was built. Here's the evidence, and why we decided not to "improve" it.
One mirror, one blind plug
Open the factory parts list for a BMW R60/2 and go to the MIRROR group (51). You'll find exactly three lines: the mirror itself, part number 51 16 2 072 296, quantity one; its mounting hardware; and a blind plug, part number 32 72 2 072 220, M8, quantity one.
That's it. One mirror, threaded into the left clutch perch. One plug, threaded into the empty hole on the right perch. The same applies across the /2 family: R27, R50/2, R50S, R60/2, R69S and the US variants. Munich never fitted a pair.
So there is no right-hand Stan Rise, and there won't be one. A right-side mirror would be a modern invention wearing a vintage costume, and it would look wrong to anyone who knows the bikes. If you do want a mirror on each side, the Stan Square pair mounts on the headlight ears instead, which is the period way to do it.
Why the glass floats
Press the glass of a Stan Rise with your thumb and it gives slightly. That is not a loose part. It is the original retention design, and it is the reason these mirrors are still serviceable sixty years on.
Inside the stamped shell sits a conical spring and a plastic pad. Together they press the convex glass outward into a white rubber seal that wraps the edge. No adhesive anywhere. The spring keeps the glass seated; the seal keeps the weather out; and because nothing is glued, the glass lifts straight out by hand.
That last part matters. A stone chip on a glued-in mirror means a new mirror. A stone chip on a spring-seated mirror means a new piece of glass. Riders in the 1960s replaced glass as a matter of course, and the vintage BMW specialists still sell the spring, the pad and the glass as separate service parts today. We would rather the glass move a little under your thumb than have you throw a mirror away.
What we did change
Only what rust would have changed for you anyway.
The original Albert-style mirrors were chrome-plated steel, which pits and peels on a bike that gets ridden in weather. The Stan Rise stem, lock nut and stamped body are polished stainless steel instead. Same dimensions, same M8 left-hand thread, same square head on an upright 215 mm stem that puts the glass above the bar line so you see the road rather than your knees.
Everything else is left alone: convex glass, white period seal, single ball joint with the tension set by its nut. From the saddle it looks exactly like the one the bike left the factory with.
A replica that changes the design isn't a replica
We get asked, occasionally, why we don't just glue the glass and make a right-hand version. The honest answer is that we could, easily. We choose not to, because a reproduction that fixes the "flaws" of the original is no longer a reproduction of anything. We keep the design and take responsibility for the quality. To us, that is what a tribute means.
Related reading: Where to buy vintage BMW /2 parts: 10 verified suppliers and Best motorcycle mirrors for BMW Motorrad: fitment and thread sizes. 日本語版はこちら: 1970年以前のBMW /2にミラーが1本しかなかった理由.
Fitment: BMW models with an M8 left-hand thread clutch perch, pre-1970: R27, R50S, R50/2, R50US, R60, R60/2, R60US, R67, R67/2, R67/3, R68, R69, R69S, R69US. Not for 10 mm modern perches. Sold as one left mirror.
Sources: BMW R60/2 parts list, group 51 (Mirror), via Bob's BMW microfiche and partsss.com.
KiWAV is not affiliated with BMW. The Stan Rise is a stainless replica of the original design, not an original BMW part.
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