Before you install a stem grease all the bolts lightly at the threads only. This will prevent squeaks, increase life of the bolts, help prevent stripped bolts and help prevent seizing. Do not grease the underside of the bolt head where it comes in contact with the stem face. Greasing the bolt head will cause the stem bolts to be easily overtightened resulting in stripped and bent bolts. After you grease all the bolts spin in the two stem clamp bolts a few turns. Next make sure you remove any grease or residual manufacturing lubricant from the stem clamping area.