Busch & Müller Cycle Star 80

The Busch & Müller Cycle Star 80 has been the default mirror on serious trekking and touring bikes in Germany and the Netherlands for decades, and not by accident. B&M has been building bicycle lighting and accessories in Meinerzhagen since the 1960s, and the Cycle Star line is their answer to a simple question: how do you get a stable, sharp rear view on a bike ridden on real roads? The answer is a turned aluminium expander bolt that clamps inside the bar end, a short gooseneck with a rubberised ball joint, and an actual 80 mm convex glass lens. On a Koga WorldTraveller or a Stevens Galant — or increasingly on a speed pedelec where Dutch law demands rear visibility — this is the mirror the shop nearly always recommends. The difference against a plastic mirror shows within five minutes of riding. At 25 km/h over cobbled stretches in an old city centre, or across the broad concrete slabs along river dykes, the image stays usable and sharp, where a bar-clamp mirror halfway along the handlebar vibrates into a pastel smear. That is physics: the bar end is the point of least resonance on a typical handlebar, and the short gooseneck keeps the lens close to that stable pivot. The 80 mm convex glass offers roughly 25 degrees of field of view, plenty to recognise an approaching e-bike or car at a safe distance. For speed pedelec riders legally required to check rearward before merging or turning, that stability is the difference between adequate and genuinely pleasant.

Against direct competition the Cycle Star 80 sits in an interesting middle ground. The Mirrycle (an American import popular with mountain bikers) has a longer adjustable arm but a smaller lens and feels more plasticky. The larger B&M Cyclestar 901 offers an 80 mm lens on a much longer stem — better vision, but more fragile and prone to catching in crowded bike racks. The Zéfal Spy and other bar-clamp mirrors are cheaper and more flexible to mount, but match neither the optics nor the build quality. For riders on trekking bikes, trekking e-bikes or speed pedelecs scanning rear traffic daily, the Cycle Star 80 remains the rational pick after decades.

Honest caveats: the Cycle Star is not a universal fix. If your bar plugs are glued in — and modern carbon drop bars and some smooth aluminium city bars are deliberately bonded — you need to ask a shop or simply choose a clamp mirror instead. On narrow Dutch city-bike bars (around 54 cm) the extra four centimetres of overhang can be just enough to get clipped while parking between cargo bikes at a busy station. And the expander bolt needs to be tightened to even tension during installation — too loose and it creeps out on cobbles, too tight and you mar the inside of the bar. Take five minutes over it.