Can the steerer tube touch the rubber locknut seal on a threaded headset?

[rogerzilla]

Park's webshite unhelpfully only shows a locknut with no seal (only old Raleighs and really crappy headsets have none).  I measured super-accurately when choosing a headset - perhaps too accurately - and I have a steerer that makes contact with the seal, but not with the metal narrower top of the locknut.  I can chuck a 1mm spacer in, but do I need to bother?

[Brucey]

wheteher there is a 'seal' fitted or not there are almost invariably no threads in the last ~1.5mm of the locknut so there is absolutely no point in being 'super accurate' when measuring up your steerer.

Plenty of excellent headsets have no 'seal'  and (of course) if there is one fitted and it is pushed upwards by the end of the steerer it cannot make as good a contact with the stem.

You should fit a spacer.

cheers