Steering geometry

Steering geometry describes how the frame, fork angle and front wheel are positioned relative to each other. The key values are rake (steering head angle), trail (the distance on the ground between the steering axis and the tyre contact patch), fork offset (set by the triple clamps) and wheelbase.

Quick, light steering comes from steeper rake, less trail and a shorter wheelbase, as on sport and motocross bikes. Stability at speed comes from more rake, more trail and a longer wheelbase, as on cruisers and touring bikes. Tyre size and profile also change the effective geometry.

Geometry changes with ride height: raising the rear or sliding the fork tubes up in the clamps steepens the rake. Adjust in small steps, keep notes and check that nothing touches at full lock or full compression.