At the high end, Extralite RoadStem UL2 and Syntace F99 260 are the weightweenie choices, mid range people like the Ritchey WCS 4-axis and the KCNC SC Wing Scandium is pretty light too. Lower down, there are several 3D forged stems which are light - Planet X, PostModerne Smica for example - and some CNC machined ones like ProLite Pelmo. Any of those should be <140g in 100mm length, with the very light ones being <100g. Thomson don't even list any 26.0 stems any more, but when they did they were in the 200g area.
Budget/length?
At the high end, Extralite RoadStem UL2 and Syntace F99 260 are the weightweenie choices, mid range people like the Ritchey WCS 4-axis and the KCNC SC Wing Scandium is pretty light too. Lower down, there are several 3D forged stems which are light - Planet X, PostModerne Smica for example - and some CNC machined ones like ProLite Pelmo. Any of those should be <140g in 100mm length, with the very light ones being <100g. Thomson don't even list any 26.0 stems any more, but when they did they were in the 200g area.
I've got a 110mm Planet X at 113g and a 120mm Ritchey WCS 4-axis at 132g for sale in this thread https://www.lfgss.com/thread28042.html