Miss thumb shifters? Converting a drop bar bike to flat bars? These easily transform bar end (aka barcon or TT) shifters into thumb shifters. The shifters are not included, but are readily available in 8 through 11-speed versions, and many have an option for friction-shifting.
Thumbies bring back the thumb shifting of old, and we think it makes shifting more precise and smoother. These feel much better in our opinion than trigger or twist shifters.
Thumbies have a hinged clamp for an easy installation and fit handlebars with a diameter of 22.2mm or 31.8mm. The 22.2 models fit mountain bike handlebars and the 31.8 mount to the stem clamp area of a drop bar. The clamp is raised up to give clearance for hydraulic brake levers.
We currently make Thumbies to work with Shimano shifters only. They have a shifter mounting boss that fits Shimano bar end shifters and most Shimano downtube shifters.