Originally Posted by atombikes

If you have MTB-2ized shifter/brakes as I do (22.2mm diameter at the clamp) a company called Crow Cycle sells bullhorns that size (22.2 bar/25.4 stem clamp). This is what I used on my bike.

Originally Posted by Rowan

Just a little bit of advice on bull horns. Check to ensure the outside diameter of the tubing from which they are made is compatible with the clamp diameter of the levers you intend to use. The same applies to the internal diameter. I went through the process in fitting the bull horns to my new Bike Friday. I was aware of the diameter of the MTB shifter clamps, and then went hunting on eBay and other places to find them.