Just serviced the headset on my SCR when I have reassembled I have noticed there is a gap of 2-3mm between the fork crown and the bottom of the headtube. Took everything apart again reassembled nothing being obstructed. Gap still there. If you are close to a Giant SCR at the moment could you just have a look and see if you have a similar gap. Have emailed Giant but not sure how long it will take for them to reply. If that gap is supposed to be there its a bit cacky as its easy for dirt and water to get through to the bottom bearing race.