How to Install Inline Bearings

Place your wheel on a flat hard surface and position the bearing on the hub of the wheel.  When pressing your bearings into the wheel hub, use a proper skate tool, and be firm but not rough. Otherwise, you can easily damage the seals and cages.  Once you seat the bearing on the first side, flip the wheel over, insert the spacer, and press in the second bearing.  If you are using a bearing with a built-in spacer it is not necessary to insert the spacer.  You can also use the Bont 125mm Inline Skate Bearing Press/Puller.

Install the wheel unit on your skate, insert your hex tool all the way into your wheel axle and tighten the axle until snug. Do not overtighten as the axle is typically made of softer aluminum than the frame and you can damage the axle.

The inner race of standard 608 or 688 bearings has an inner diameter of 8.0mm, with a small manufacturing tolerance. For the greatest wheel and bearing precision, axles should have a diameter of around 7.95mm – 7.97mm.