RockBros Loud Bell

The RockBros Loud Bell is the budget alternative for riders who want one thing: to be heard. RockBros is a Chinese accessory brand that has built huge European sales via Amazon and AliExpress by being unashamedly cheap. The Loud Bell is a compact aluminium cylinder with a lever that strikes a sharp metal ball against a hollow internal cavity. The result: an almost unpleasantly loud sound that cuts through car traffic and MTB wheels on gravel. In our testing it regularly measured around 95 dB at one metre — roughly ten decibels louder than the Spurcycle, audibly a different category. It is simple to use. Mounting uses a clamp that handles both 22.2 and 31.8 mm bars thanks to an included rubber shim, and you can install it with a hex key in five minutes. On a mountain bike in wooded hills or on a trail in the southern provinces, this is exactly the bell you want: hikers on shared paths hear you from ten metres away and step aside. For e-bike riders moving at 25 km/h on fast cycle paths past pedestrians on shared park paths, that volume is sometimes a safety issue. And for delivery couriers weaving through tourists in old city centres daily: few bells are more effective at clearing a path.

Against the competition the RockBros plays its own game. None of the premium bells (Spurcycle, Crane, Knog) come close to this volume, but then again none of them claim to. The Cat Eye OH-2400 Oh! is similarly cheap but clearly quieter. The Widek Decibell 80 is a notch louder than the premium category but still 10 dB below the RockBros. The true competitor is really a whistle or horn — but those are not legally accepted as a bell substitute in the Netherlands, whereas the RockBros does meet the legal bell requirement. For riders chasing raw decibels at a low price, it largely stands alone.

Honest on the weaknesses: those 95 dB cost tonal quality. Where a Spurcycle carries on its pure fundamental, the RockBros tone is sharp, short and frankly ugly to sensitive ears. It works — but you will not enjoy it. Quality control is also patchy: roughly one in five units from Amazon batches arrives with a rattling spring or a stiff lever. Cheap here also means: no lifetime warranty and no spare parts. After eighteen months to two years of daily use the mechanism gets noticeably stiffer. For 10 euros that is no disaster — just buy a new one. For MTB riders, delivery couriers and e-bikers who want maximum warning for minimum price, it is the logical pick despite all those caveats.