steering stem bearing

You need a bearing separator and puller to get it off the stem.

If you plan to reuse it, and simply want to grease it, clean it and grease it without removing it from the steering stem.

To remove the bearing, you press the steering stem out of the bottom triple clamp from above. Then you flip it over and press the stem back in place. Then you can install a new bearing on the stem with the press.

A 20-ton hydraulic press will make short work of it. I've changed several of them this way myself.