A common mistake with identifying headset bearings is using the 1″1/8 or 1″1/2 measurement reference as used by the industry, the 1″1/8 or 1″1/2 refers to the steerer on the forks.
All headset bearings have metric dimensions and should be identified by using the included diagram.
The two important measurements are the outer diameter and height, its these two dimensions that allows the bearing to be seated in frame correctly.
The inner diameter is not imperative as different manufactures vary there’re inner diameter by 0.1 – 0.3mm. The reason for this is that the forks do not actually touch the inner race, the bearings points of contact are the chamfered edges.
There are two common angles used for headset bearings 45/45 and 36/45:
45/45 is the most common and is found with most headsets from recent years. Both races are either metal or black in colour.
36/45 is not as common but still relatively popular. In most cases the manufacturer will blacken the inner race so as to indentify it as 36/45.
If you’re having trouble identifying please contact us and we can help.
If you’re having trouble identifying your bearings please contact us and we can help.
If you’re a bike shop or bike mechanic and change headset bearings on a regular basis we would recommend a good quality vernier calliper (Oxford Instruments). If you choose a digital vernier don’t choose a cheap one, they can give false readings and have you chasing a bearing that doesn’t exist…we know from experience.