when installing the headset and stem, you need to tighten the cap bolt on the headset and then torque down the bolts on the stem. Once the stem bolts are torqured down correctly, I like to back the stem cap bolt about a 1/8 of a turn just to take the pressure off the bolt but it is still tight. make sure you have enough spacers so the cap is sitting on the spacers and not the fork's steerer tube.

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