Cone Wrench Essentials: How to Adjust Cup-and-Cone Hubs

Cup-and-cone hubs are still widely used on many road, gravel, and touring bikes thanks to their serviceability and smooth rolling performance. Adjusting them correctly is essential for preventing premature bearing wear, eliminating hub play, and ensuring long-term reliability. Cone wrenches are the key tool for this job—they allow you to hold the cone in place while tightening the locknut without damaging the bearing surfaces. This guide explains how to use cone wrenches properly and how to achieve the perfect hub adjustment.

Begin by removing the wheel from the bike and cleaning the axle ends so you can clearly see the locknut and cone. Cup-and-cone hubs operate using loose ball bearings that rest in a precisely machined cup inside the hub shell. The cone threads onto the axle and adjusts the preload on the bearings. The locknut holds everything in position. If the cone is too tight, the hub will feel rough and slow; if it’s too loose, you’ll get side-to-side play that can damage the bearings and cup.

Select the correct size cone wrench. Common sizes include 13mm, 14mm, 15mm, and 17mm. Cone wrenches are thinner than standard wrenches, so they can reach the narrow flats on the cone. Use a second, regular wrench to hold the locknut. Start by loosening the locknut while holding the cone steady with your cone wrench. Once the locknut is free, rotate the cone slightly to adjust bearing preload.

To check the adjustment, hold the axle with your fingers and spin it. A properly adjusted hub should spin smoothly without resistance and without any side play. The goal is “just enough” preload—tight enough to remove play but loose enough to allow free, smooth rotation. Because tightening the locknut changes the cone’s position slightly, you often need to make small compensations: adjust the cone slightly looser than final tightness, then tighten the locknut and re-check.

Repeat this process until the adjustment is perfect. For front hubs, the process is usually straightforward. For rear hubs, the freehub body can make access more difficult, but the principle is the same: use the cone wrench to set preload, then secure the locknut. Always check both sides of the axle for correct symmetry, and verify that the axle sits straight in the dropouts after reassembly.

Some common issues include over-tightening, which causes grinding and accelerated wear, and under-tightening, which leads to play that can damage the cup and deform the bearing surfaces. If you hear clicking or feel roughness even with good adjustment, the bearings or cup may already be worn and require replacement.

Below is a simple checklist you can copy directly into Word to help maintain consistent adjustments:

Cup-and-Cone Adjustment Checklist

Step	Status	Notes
Locknut loosened	Yes / No
Cone adjusted	Yes / No	Slight preload applied
Axle spin test	Smooth / Rough	No resistance?
Side play checked	Yes / No	Should be zero
Locknut retightened	Yes / No
Final check with wheel installed	OK / Needs readjustment