I guess the OEM rates for the stem nut won't work with tempered bearings...
Normally you'd probably now need a spring scale (I'm sore someone made a write up on this somewhere...)
I'd do the following check we use on cornfirming proper rates/funtion/integrity on OEM head bearings:
- jack front up till rear wheel touches the ground
- move front wheel from 'straight' to about 1/2-way tilted and let go; the steering should it not 'stick' there (too tight), but move slowly until it hits the steering limiter; same to the other side.
If the steering literally 'falls' through without any resistance, it seems too lose, so give the nut a small tweak and check again.
But lets see what others, who've already dealed with those roller bearings, think about that??
The lock-nut shall not be torquered, just twist it on till it touches the securing plate slightly, then twist back till the first gap matches the tabs of the tin, bend up/into done (its all fixed with the upper tripple-clamp)