Stiction

Stiction (static friction) is the resistance that must be overcome before two surfaces start sliding against each other. In motorcycle suspension it occurs mainly in fork seals, dust wipers and bushings, and in shock seals. High stiction makes the suspension feel harsh over small bumps because it does not start moving until a larger force arrives.

Causes include dry or dirty seals, worn or poor-quality bushings, bent fork tubes, wrong fork alignment after fitting the front wheel, and old oil.

Reduce it by cleaning the seals and wipers, servicing the fork with fresh oil, using low-friction seals and coatings, and loosening and retightening the axle and clamp bolts in the correct order so the fork legs are parallel.