Bought these knowing that they would require some modification to use on my FZ-09, which comes with threaded bar ends. They were not only too short to extend far enough into the bar, but the rubber was also a little too fat to fit in the threading. I hit McFadden-Dale hardware and found set screws of an appropriate length, and some nut-couplers. I unthreaded the stock set screw and threaded in the short piece, topped with the coupler, then rethreaded the stock one into that. I then threaded on a flanged nut identical to the one that comes with the bar-ends to serve as a lock nut/spacer. I reinstalled the rubber, washer, and end nut, then trimmed the rubber down with utility knife (go slow, be careful) to slightly larger diameter than the washer. It slipped right in, and tightened down as normal. Because the stock bar-ends have a bit of a shoulder on them that spaces the bar end away from the throttle housing, I cut spacers off of an old carbon MTB bar, which gave it a nice little carbon accent between the end of the grin and bar-end.
I had to shave all of the back side off in order to get it the fit. Vice and angle grinder made quick work of the aluminum. My bars have a piece welded in the ends of them.I Bought the gold ones and i love the weight and color of them. I"ll update later and post some pictures.
I had to get creative in order to get these on my bike. Haven't ridden with them yet so time will tell if I did it right. Some instructions might have been helpful.
Instructions can be found here: http://drivenracing.com/sites/default/files/public/instructions/Driven%20instruction%20bar%20ends%20dbew-xx.pdf