Hey everyone

I am finally getting round to building up a Peugeot 531 Pro ("Aneto") frame from 1986 that I bought several years ago.

First step is installing the new threaded headset which has balls captured in cages.

For some reason, I am thinking the correct adjustment here should be a slight pre-loading of the ball bearings.

I seem to remember an idea that this engages more balls in contact as well as prevents any play wearing out the races through repeated micro impacts.

Does this seem reasonable ? (pre-loading the bearings when adjusting the headset)

I snug it up to just the point where I feel resistance in the steering. Then I tighten the two nuts together, and since this process slightly backs off the lower one, it usually ends up perfect.

No wobble with no resistance to steering is your goal. You can get away with a bit more overtightening with cartridge bearings than with balls. Too tight and it'll feel weird steering.

I test it by grabbing the top tube near the front and lifting. Then let it tip side to side. Any binding, I loosen it.

Headsets should have no resistance to turning. It’s usually easier to finalize the adjustment with the bike assembled and the front brake locked. Rocking the bike forward and back will highlight any play.

A point to remember: adjust *after* installing the stem.
The steerer will distort slightly when you tighten the quill, and if you had the headset perfect before it won't be anymore.

Wait, people do that? That's like eating dry toast then taking a bite of butter.

^^^ This. Adjust so you just eliminate the play. This results in easy turning of the bars and maximum bearing/headset life.

A itty bitty bit of play is better than tightening them a teeny tiny bit too much. But not so much that you feel it when you are riding.

Unlike Iride01, I adjust headsets with no play. Install it in the stand initially. Then put the bike on the floor. Hold the front brake and rock the bike back and forth to detect play. Hold the front wheel between my legs so I can use one hand on the wrench on the adjustable and the other hand on the wrench on the locknut. It's a good idea to adjust it too loose at first (locking the locknut) and then tightening the adjustment very slightly (again tightening the locknut). If it's still loose, tighten it again, still very slightly.

Some good tips there, some of which I had forgotten but will now use when I instal the headset. Thanks.