I recently bought a used Birdy 7. The headset is a bit loose. It could be that the bolt below the headset needs to be tightened. I plan on overhauling it anyway.
The fork is clamped to the stem. Should there be any grease where the stem and fork meet. They are Al so I doubt they will rust, I think no grease is necessary.
Does the headset use 5/32" bearings? I wonder if they have some sort of metric size. The bearings in the headset seem to be 5/32.
I noticed a clamp just above the top headset bearing race. What does it do? Can the location of the headset be changed?