I recently purchased a Titan steel track stem, and am not sure about the bar sizing. From what any searches say, they are 27mm, but with my cheap calipers, and no tension on the opening, I'm getting 26mm. Were all of them 27, or some more like a 25.4? If it is indeed a 27, can another bar be shimmed safely? Thanks for any info.

My Kint bars that fit the Titan stem are 27.0. The stem is 27.0 at the clamp. I'd suspect that someone put the squeeze on your stem, but I dunno for sure. I have never had first-rate results with a shimmed bar; it is safe but mine always seemed to be squeeky creaky.