I was packing up an old set of WP forks from a 560 I had got in a trade (I'm the sucker) and a guy I had been talking with for a while offered me this old KTM Equiptment tank bag off a 990 adventure minus the zippered attachment points for the forks straight up. I said hell yes and it was on.
I bought 6 feet of 1" Nylon Webbing from ACE, some heavy duty nylon thread and got to sewing.
Needle drivers are a great investment if you are planning on sewing nylon. This stuff is TOUGH! These tools can be found at most surgical supply places, but are more commonly found where any fishing gear is sold. The surgical quality ones are better, but anything to give you a good grasp on the needle as you punch it through three layers of thick nylon.
Essentially I just folded the webbing in half and sewed around the existing zipper attachments. I left four straps coming off at four attachment points a the front and back corners. I then put on some ABS strap clips from ACE on the four straps.
I used 18" velcro 1" straps that I could easily take off the bike if need be to clip into the bag. This allows for quick access to fuel up just by undoing the clips and not the whole strap set up.
It does limit forward movement on the seat a little bit, and standing is not as comfortable, but I gladly sacrifice that for carrying 3 liters of fuel, a map holder, a tool roll, an emergency rain suit, and my cable lock.
This bag has opened up a whole new group of roads to me with the extra fuel I can carry. It also sits center mass over the tank so I don't notice the weight as much as I did with saddle bags.
COSTS: KTM Equipment Bag -$Free although it does resemble this FAMSA bag Nylon Webbing 6' 1": $1 a foot x 6 from ACE = $6 Strap Clips: $1.49 x 4 from ACE = $6 18" Velcro 1" loops from ACE $3.99 x 4 = $16 Total: $28
