Trimming the steering stops on the Concours is one of those things that makes your stomach hurt until you're done. Then you wonder why you didn't do it sooner.
1) Get access to steering stops by removing the headlight bezel. Some remove all the plastics, which gives you more room, but you don't need to.
2) Take a flat tipped, angle cut (about a 3 mm), Magic Marker (about a on inch tube). Make a vertical stripe holding the the tip flat against the steering stop at the edge of the stop. This will give you about a 3 mm black stripe.
3) Get a dremel with a small grinding wheel (one specifically for aluminum works best, but not required). Start from the steering stop grinding, A LITTLE AT A TIME, the black stripe away.
CHECK MANY TIMES THAT YOU DON'T TAKE OFF TOO MUCH. YOU CAN CHECK BY MAKING SURE NOTHING COMES IN CONTACT WITH THE GAS TANK AND ALL BRAKE LINES AND CABLES ARE CLEAR. YOU CAN CHECK THIS AT ANY TIME BY MOVING THE HANDLEBARS SIDE TO SIDE AGAINST THE STEERING STOPS YOU ARE GRINDING ON.
4) Reassemble, stand back and smile, or cry.
This modification, depending on you skill level, will allow you to turn 17 foot circles.
THINK ABOUT THIS BEFORE YOU START, THERE IS NO REVERSING THE PROCESS.