Not sure what sort of shifters you are using, but perhaps you need a shim? I know that the Profile brake levers fit into their bars without using one, but they include a round shim for use in larger ID bars....

hi phil, I'm using Shimano DA bar-end shifters. The ends seem too small for the C2 bars. I think you might be right....but where can I get those shims???

There are no shims for that, that I know of, however you can cut up a soda can and make one. Here is another thought though. Those DA shifters, 9 or 10 speed, should fit the Syntace bars without a shim, I have installed a few of them myself. The way the shifters stay in place is by the use of an expansion nut. Take a 6mm hex and insert into the shifter base. They tighten counter-clockwise, not clockwise as most things. Put a few turns on it so it is not loose and then put it into the bar, Then continue to tighten until it is secure. I hope this helps.

pjrubin:

THANKS! It worked!! Awesome!! I just know that some STer would be able to solve this and save me a trip and some $$ to the LBS :)

Was thinking about whether or not I should mention the reverse-direction to tighten thing, but I didn't because I figured you must have noticed it to get them off in the first place! At least it all worked out eventually...