1) Install Bearing Cups
Before you begin, note that many modern bicycles do away with external bearing cups altogether and use an integrated cup system. If your bicycle has this style, simply apply grease to the integrated cups and set the bearings into the frame by hand. Integrated threadless headset bearings come in two popular sizes (the International Standard and the Campagnolo Standard) and are differentiated by having different bearing contact angles. Refer to your bicycle’s instructions to make sure that you have the correct bearings.
If you do not have integrated bearing cups, follow these steps:
• Lightly grease the head tube of the frame where the headset cups will contact. If you have a titanium frame, use an antiseize compound.
• Slide the top cup onto the upper race of the headset press, and insert the headset press through the top of the head tube.
• Slide the bottom cup onto the lower portion of the headset press, and install the lower race of the headset press. Hold the bottom of the headset press with a wrench so that the tool does not spin as you press in the headset cups. As you install the cups, make sure that the cups are straight and are not binding in the head tube.
• Stop when the cups make flush contact with the head tube. Do not overtighten because the cups can be damaged if they are pressed after they are firmly seated in the head tube.