I have the latest Downtube 9 FS as my demonstrator now, and with Smithfield Nocturne looming, I decided it was time for some mods to my older IXFS. I'd already fitted a Brooks B17 Champion, but I had more in mind. For this round of mods, I replaced the original bars with some older drops (older drops in this country had the same clamp diameter as is now used for MTB bars, so they fit), got some suitable levers for the V brakes, and fitted an old Suntour bar end shifter I had. Finished it off with Velo Orange elkhide bar wrap to match the seat. I find the standard gearing too low; I seldom use, and never need anything below about 4th, maybe 3rd, and find I spin out too easily on downhills, so I fitted a 52t chainring I had laying around, and also put some Marathons on, the 1 1/2 inch ones which are rated to 100 psi. Only a couple of issues; somehow I used a different stitch on each side of the tape, and I realized part way through the process that I'd actually got the levers on the wrong sides; no biggie really. Secondly, I should really have fitted the old 105 cranks I have around, as the torque a guy my size can put on a 52t chainring in the highest gear flexes and bends the spider on the standard cranks (never had any trouble with them in the standard guise).
That aside, it's wonderful. Gives me a more aero riding positions on the hoods, without being too low, and then the hooks get me right out of the wind. Of course, the adjustable stem means I can be even more aero if I choose. The gearing feels great, flexing aside, and the bar end shifter, despite being designed and manufactured in the 5 speed era, shifts right across the 9 speeds no problem. Do I have the handsomest IXFS now, or what?