His rear rack isn't the stock one and mounts more to the rear sub frame looks pretty beefy.

 

that may help things then. after looking at the pic closer, it looks like most of his weight is where the passenger's weight would be. so it's probably better supported in that area.

 

Yeah, the rack is what makesitall possible. Before I bought the rack, Iused to put the bag entirely on the seat.

This particular rack actually bridges the rear subframe to the seat rail making that whole area hella strong!..Way better then stock. The way Kawasaki attaches their stock rack doesn't make much sense to me.

I just don't think the WR would be as accomodating to such things and I don't wan't to re-invent everything a second time, now that I've go everything how I want it.

Besides, I think a big, wide rack wouldlook goofy/er on the WR.