Hi!
so here is your traditional threaded headset:


the locknut and threaded top race have flats for using a wrench to tighten/loosen.

HOWEVER, over hauling a friend's trashed old road bike (which i believe is japanese. no clue as to make), the locknut and threaded top race DO NOT have the hexagonal flats im used to seeing, BUT they are perfectly round with the exception of 3 notches with which im assuming you need a special 3 pronged tool.

any info on this type of threaded headset?
how to remove/loosen/and/or tighten?
do i need a special tool? or?

thanks!