[650]

It's the bearings. Too tight will cause wobble and weave at low speed. Too loose and you'll get clicking and vague steering. You can also encounter the feeling you're getting if the forks are twisted in the clamps or the spindle is too tight. But my money's on the bearings.

Bearings needs adjustment with the front wheel off the ground. You should also loosen the lower clamp pinch bolts so the forks can turn in the triples while making the adjustment.

Torque settings are high for the lock nut and the top triple clamp.

40Nm tends to be the torque setting for the steering nut, 80Nm for the lock nut, 90Nm for the top yoke.

Feel is important on the steering stem, at least more so with tapered bearings than the stock roller bearings...so are you definitely using roller bearings or have they been changed out for tapered? Tapered require a 0 preload so the steering nut should only just be nipped up from finger tight.