I am wondering how it is the 3ttt bars fit the Cinelli stem. I have had them since buying the bike in 1978 with no issues. In fact I never thought there could be an issue until I looked into getting another stem and finding out about the different diameters. The 3ttt bars flare out to a larger diameter at the clamping area, and tightening the clamping bolt on the Cinelli stem has presented no difficulty.