you can shim a 1"bar, to fit in a 1.25" stem.. and 26>31.8.. [but not the inverse] (1.25"=31.75mm..)

I have Trekking and flat bars that are 1", center, 7/8" MTB controls fit.. [22.2mm]


now if you are leaving out you want aero-carbonfiber drop bars,
and get in a lather over the latest race bike gear, the Pro's ride, that is a different set of needs..

C&V Collectible Italian stuff , uses 26, older Cinelli 26.4mm




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