Yep. I've done a little math on the available numbers, and it appears to me that the 701LR with a full tank weighs about 380 lb. Add a decent wind screen to it, beef up the "subframe" and add passenger pegs, and it will probably be within 10 lbs the same weight as the dual-disk 640 Adventure (remove one of those disks and calipers and the weight drops by about 6 lbs). The stronger and smoother engine would be a plus, but it won't be a lot lighter. Maybe 15 lb lighter if you're okay with no pillion capability and no pannier racks.