You've thrown away a shim, or something used to compensate for the difference in clamp sizes of your bars and stem - the stem will have a bigger clamp than your bars, so without the shim your bars feel loose. No amount of tightening will change it.
Just make another one using a strip from a can to plug the gap.
You've thrown away a shim, or something used to compensate for the difference in clamp sizes of your bars and stem - the stem will have a bigger clamp than your bars, so without the shim your bars feel loose. No amount of tightening will change it.
Just make another one using a strip from a can to plug the gap.