John, I forgot to add...
Though the Cresswell ratchet should fit the handlebars directly, the mount I've described and pictured above would offset it from the 'bars enough to allow easy shifting on drops. I did not go this route on my own Nomad 'cos I used Rohloff's own rotary shifter, and decided it was an easier reach to the top-mounted T-bar. If I went the Cresswell/Ovo Tandem route, I would mount the ratchet shifter on one of these stubs, lagged directly off the inside curve of the handlebars.
Looking at the YouTube video of the ratchet shifter I linked to above, it appear one needs to have clearance to approach from below and above if it is mounted to the inside of a handlebar. I don't think co-locating it (or nearly so) with the brake lever would do, but back toward the curve a bit should do just fine for shifting ease.
Oh! One last thing*...though my quill stem is 22.2mm, the same stub could be made to fit a road-diameter handlebar by simply making the curved mounting face with a little larger radius. I used a road-diameter brake clamp, so it would work in any application. The stub I made in the photo above used a section of road-bike drop-'bar; the one on another bike uses the 22.2mm MTB 'bar I had on hand at the time.
Best,
Dan.
*EDIT: Nope, not the last;
an addendum is needed to answer questions PM'd or emailed about the composite photo I attached to the last post. I'll answer here to save time:
• Yes, I engraved the stem myself. Painted it, too, with a baked enamel finish.
• The tall headset nut is a Sugino High Column Nut, designed to further brace a tall quill stem against heavy loads like a handlebar bag or reefing on the 'bars when "honking" out of the saddle. it is sealed with an o-ring to help prevent sweat from corroding the stem/nut interface. No, it won't work on a threadless stem, nor is it needed there 'cos a 1-1/8" threadless steel steerer and clamp-on stem are much stiffer than a small-diameter aluminum quill stem in a 1" threaded steerer.
• The unusual looking headset is a Stronglight Delta roller-bearing model; essentially an A-9 in a prettier, better finished anodized external cup set and with neoprene weather seals added. The roller races are interchangeable, I did buy a half-dozen extra bearing/race sets, and no I don't have any extras to sell on. No, this headset won't work on a threadless steerer.
• The cable stop you see is reversed so it makes a parking brake, locking the front wheel for convenience and security while at rest. A subsidiary Dia-Compe #9871 quick-release mounted on cantis' straddle cable handles primary release duties. Yes, the same setup would work on a Club Tour or any Thorn equipped with cantilever brakes and a cable stop so long as you the q/r stop can be reversed in function. Yes, there have been q/r cable stops made for threadless stems, but I don't know where they are currently available.
• No, the PlanetBike Protege 9.0 computer has no external buttons; the case
is the button. Yes, it is waterproof. No, it is not perfect; the average speed is figured on a 10-hour time base, after which it shows an Error code which irritates me mightily, but I like the rest of it.
• The handlebar covers are Morgan Grips by Morgan Concepts, late of Coeur d'Alene, Idaho. They are ergonomically shaped and very comfortable on long rides on rough roads. They weigh a heavy 10.5oz/300g all by themselves and are a bear to install; even worse to reinstall as they must be glued and stitched on. They ceased production in the mid-'80s. The patent is here:
http://www.google.com/patents/US4522083 There are no more left to buy. Anywhere. I tried. Really!
• Yes, the tape under the clamps prevents scratches and the possibility of galvanic corrosion between dissimilar metals. Yes, I could have done it more neatly.
• The mysterious bracket in the upper-left is for a SkyMounti inclinometer. The one atop the stem is for a Garmin Oregon 400T GPS. The blue thing at the top of the left-hand photo is an LED flashlight in a TwoFish bracket. I use it to remain visible at stops, since this bike does not have a standlight with its dyno lighting.