This Cockpit Mount Kit is designed to attach to a 7/8in Vertical Tube (22.2mm) tube (the diameter of your handlebars where the controls attach). The mounting clamp is 1/2in (12.7mm) thick, so all that's required is 1/2in of reasonably straight tube to clamp to. Because of the strength of the clamps, we don't recommend clamping to Carbon Fiber tubes. Other than that, if you have 1/2in of clear space on a 7/8in tube that's either straight or not curving very much, you can attach this mount. In most underseat steering applications, you'll attach it just below where the brake lever clamps on.
The double ended clamps hold the centers of the tubes 2in (50.8mm) apart. With the two clamps in this kit joined by a central pivot tube, the T Bar where your accessories will go can be anywhere in the range about 0 to almost 4 inches (101.6mm) away from the tube you clamp to. The T Bar is 5in (125mm) wide and 9 in (225mm) tall. It's asymetric so you can point it inboard or outboard. The link/pivot tube is 1.5in (40mm) tall. You are free to mix and match and rearrange the clamps, pivot tube, and T Bar to get the perfect location for your accessories.
By putting the right amount of tension on the clamps, you'll find it's very easy to move things around and find the ideal position for everything. Once you've determined your ideal position, just tighten the clamps to lock everything in place.
The T Bar is 7/8in diameter, so anything that's made to attach to a handlebar will be happy there. To attach a mirror inside the T Bar, simply remove one end cap and install the mirror as if it were on the end of a regular handlebar.