While we're on the subject... I am seeking double-clamps/stem-extender/riser that is in the range of perhaps 75mm center to center. Looked all over amazon, can't find what I need; Stout looking ones are shorter, and long enough ones look thin and flimsy; It needs to be stout enough to handle full handlebar climbing torque, not just provide a place to mount accessories. It needs to be two parts, to space apart. Application:

Raising only a clip-on aero bar from a flat bar, for comfort while taking pressure off hands. Current clip-on has forearm pads too close together, but at least bars come from top half of the handlebar clamps, so could just raise, right? Profile makes 70mm spacer/riser but says incompatible with Century bars, even though they look a perfect fit, then I realize why: They are skinny laterally, so raised up 70mm plus the side wings for the pads and under arm pressure, it may put too much moment on the riser bolts (unless the wings were a one-piece span).

I have a different set of profile clip-ons, Airstryke 2000, with flip-down wings with pads that are far enough apart, but the bars attach to the bottom half of the handlebar clamp, so if I use 75mm risers, those raise just the pads and the bars will need to be tilted up at a bad angle. Plus same incompatibility issue as above.

So the plan is Airstryke 2000, double clamps on flat bar just outside of width of aero bar clamps (which are right up against both sides of the handlepost stem now and can't go wider as one piece bar), facing up, holding a short bar that the Airstryke clamps to between the double-clamps, raising the entire aero bar, but not my flat bars.

Further complication: Due to where the flat bar tapers, and I can't clamp on that, I may need the double-clamps to be 22mm diameter as the flat bar is further out, not 25.4mm as it is at center. I might need to use round shims to bridge that difference.

Stout, like this or similar, only longer bar center to center:

NOT like this, I think these will twist in torsion, though I may be forced to try if I can't find like above. At least they would only transmit torque from the clip on aero bars, not my flat bar:



This is 90mm, great, looks light, but currently unavailable on amazon. Notice it has parts between the two clamps to clamp around a steer tube, thus is a complete stem. But I can't use those parts, my handlepost is topped with a welded clamp ring:


... and same thing with accessory mounts added via screw holes:



Tern makes the following Andros stem, stout, FORGED, may be long enough, but expensive and heavy, though easily adjustable for folding: