I have an Ortlieb Handlebar bag. At work right now but will investigate further once I get home to see how much clearance there is wit the bracket on.
Ortlieb (and klick fix) have bar mount extender pieces that are added behind the bar bag mount
to place the bar bag further forward.
I adopted my Preference: 2 threadless stems stacked, on the steerertube..
the Lower one has a 1" tube clamped in it, to mount the bar bag there, lower..