The basic design that Profile uses all of our hubs has changed very little for roughly the past 15 years. While we've updated almost every component of the hub in one way or another, and introduced new hubshells, axle styles, and driver materials, the basic layout of the hub is the same. A BMX cassette hub from 2001 will happily accept a 2010 rear cassette axle or driver. Our MTB hubs use the same style of 4 pawl driver, the same oversized, sealed bearings, and similar aluminum center axles, so overhauling a Profile MTB hub is very similar to overhaulings our BMX hubs.

A few words about hub shims. Shims are very thin (.005") (that's five thousandths of an inch) slices of metal that were sometimes placed behind the bearings next to the bearing seats on the aluminum center axles. Some years, we made the axles a bit shorter and then used shims to make up the difference. For roughly the past two years, we've been making the axles a bit longer, so no shims are needed in most cases. If your hub is not loose, and you take your hub apart, and don't find any shims, you don't need shims. If your hub is loose, shims may make it better, or they might not make any difference. It really depends on the cause of the looseness.

One of the main causes of loose hubs is repeated overtightening by the end user. Over time, the cone spacers and/or the aluminum center axle are crushed, which causes the looseness to develop. Another frequent cause of looseness is worn-out bearings. Riding around for extended periods of time on a loose hub is only going to make it more expensive to repair. If your bearings are worn out or otherwise damaged, no amount of shims is going to make the hub tight again. You cannot get rid of side to side play in a Profile front hub by tightening the bolts more. All you're doing in that case is crushing the cone spacers and/or axle and making the problem worse. If your hub is loose, you should contact us as soon as you notice it, and we can discuss repair options with you.

The best method of installing sealed bearings into hubs is with an bearing press of the Arbor Press variety. Because the bearings must be pressed into the hub with the axle in place, most conventional bicycle bearing presses won't work. We know that not everyone needs to own an Arbor Press, so the instructions we provide on the following pages are all using as few specialty tools as possible, in the attempt at showing how to work on our hubs using the tools found in most bicycle-friendly households.

We provide these instructions as a service, but please bear in mind that if you chose to work on your own hubs, you do so at your own risk. If you are not mechanically inclined, or you have never worked on bikes before, we strongly recommend that you take your bike to a proper bike shop with trained bike mechanics for all service on a regular basis. Profile Racing is not responsible for any damage incurred by following these instructions incorrectly.