When the torque is right, this bike wrench crinkles
As any bicycle mechanic will tell you, it's crucial to apply the right amount of torque when tightening components on a bike. Too little, and the part could come off. Too much, and either the component or the frame could be damaged. That's why many cyclists use a torque wrench … and the Crankl might just be the simplest and potentially least-expensive one ever made.
Ordinarily, torque wrenches utilize a ratcheting mechanism – when the correct amount of torque is reached, the wrench's bit stops turning. By contrast, the Crankl's polymer body crinkles when the torque is right.
Users start by utilizing their existing multi-tool to do most of the tightening. They then slip that tool's bit through the Crankl's head, and finish the job by applying leverage to the other end of the Crankl. Depending on which side of the device is facing the user, its bottom beam will temporarily fold in when either 2 or 5 newton meters of torque are reached.
According to UK-based inventor Tom Lawrie-Fussey, the 20-gram Crankl should be able to perform "many hundreds" of tightenings without permanently deforming. Additionally, it's intended more to be a bring-along-on-the-ride tool, as opposed to replacing a conventional torque wrench as a full-time shop tool.
Tom is currently looking for commercial partners interested in licensing the technology, and can be reached via the link below. He believes that the device could be sold for as little as £1 (about US$1.30), or even offered as a promotional freebie.
It's demonstrated in the following video.