Tread Maintenance

My treads felt gritty and stiff with dried garden soil after rolling back across the balcony threshold. I paused on the bristly coconut-fiber rug just inside the door, letting out a short, oscillating whistle to measure the traction. Deciding on a direct solution, I locked my left tread and revved my right tread forward in a tight, stubborn pivot. Tiny dried flecks of balcony earth flicked free against the stiff fibers. I reversed the motion and spun the other way until both treads rolled smoothly without a single crunch, finally settling down on the soft rug edge for the night.