I've got the same set up from Dirt Racks. I welded up a nut behind the bar for mounting the gas cans to them and I bolt my pelican cases to the bike that way (using the Dirt Racks mounting kit). I have not done a cross-brace bar, and I have yet to crash hard on the racks/hard cases but I have dumped the bike repeatedly in the past (including more than once having the KLR tumble over top of me while crashing downhill) while using the racks with soft cases without issue. So, yes, I am wondering about the value of a cross brace verses the potential of weakening the actual rack in the process.... It is likely that I'll eventually pick up some round stock and cut/fabricate something that I can clamp to the original racks ... "one day". Yes, I am a tad worried about stress and vibration on the two mounting points over time as I ride on rough roads/trails and I tend to "ride above my pay grade" regularly.