17 mm cone spanner, Curtis Cone

You will need a tapered spanner to adjust and service the bearing play on standard tapered bearings (fitted to wheel hubs). As these special spanners are extremely flat, they fit precisely into the narrow gaps to hold the cone in place whilst tightening the lock nut – something that is not possible with conventional open-ended spanners. Do’s - Use two wrenches: For a precise adjustment, use two cone wrenches of the same size. One to hold the cone in place and one to turn the lock nut. - Adjust bearing play precisely: Cone bearings should turn easily but have minimal play within the wheel. With quick-release skewers, the bearing play must actually be slightly greater, as the tension of the quick-release skewer compresses the cone and reduces the play. - Tighten in opposite directions: Hold the cone firmly and turn the lock nut firmly in the opposite direction. Once both are tightened firmly against each other, the tension will adjust itself. - Regular maintenance: Check and grease the bearings regularly. Don’ts - Misusing as a universal spanner: Never use cone spanners on other components such as pedals or axle nuts. The material is too thin and not suitable for such high torques. - Using brute force: Cone tools are not designed for brute force. If something is stuck, it is better to use a little penetrating oil rather than prying it loose with brute force. - Using the wrong thickness: Do not use standard open-ended spanners. These are too thick to hold the cone in its narrow recess.