I put a nice 26.4mm cinelli stem on an old Trek I'm working on, and to get the ~26mm (not sure of exact size) ttt bars to fit tight, I shimmed it with a V8 can...but it's a little too thin. Are beer cans thicker, are any cans slightly thicker? A steel can would be too thick I imagine, since the V8 shim almost but not quite works.