Motorcycle tyres rarely wear evenly across their width or between front and rear. The pattern that develops is a direct record of how the machine has been ridden.
Front and rear do different jobs
The rear tyre delivers all of the drive and takes the weight transfer that comes with acceleration. It scrubs against the road every time power is applied.
The front tyre does most of the braking, and under heavy braking a large share of the machine's weight is thrown onto it, deforming the contact patch severely.
Because the loads differ in kind, the two wear at different rates and in different ways, which is why rear tyres are commonly replaced more often than fronts.
The curved profile concentrates wear
A motorcycle tyre is rounded rather than flat, so only a narrow band touches the road at any lean angle. Straight-line riding uses the same narrow strip continuously.
A machine used mostly on motorways therefore develops a flattened central section while the shoulders remain almost new, which is often visible as a distinct step.
That flat centre changes how the bike turns in, because the profile no longer transitions smoothly as the machine leans, and riders describe the steering as reluctant or notchy.
Squaring off changes handling before it changes grip
A squared tyre still has plenty of tread depth, so it passes a legal check comfortably. The problem is shape rather than material.
Tipping the machine into a corner requires rolling off the flat area and onto the curved shoulder, which happens abruptly rather than progressively.
Riders often blame suspension or geometry for this feeling, when replacing the tyre restores the original behaviour immediately.
Pressure and load leave their own marks
An underinflated tyre flexes more at the edges of the contact patch, so wear appears heaviest at the shoulders while the centre remains comparatively full.
An overinflated tyre does the reverse, riding on a reduced central contact patch that wears quickly and reduces grip in the wet.
Carrying a pillion or luggage without adjusting pressure produces the underinflated pattern even when the cold reading was correct for solo riding.
What the pattern tells a rider
Wear that reaches the very edge on one side only usually indicates a rider who habitually corners harder in one direction, often a consequence of local road layout.
A ridge or scalloped edge across the tread frequently points to suspension damping that is not controlling the wheel properly rather than to the tyre itself.
Reading the surface at each service is worthwhile because the tyre records information about the machine that no gauge or dashboard reports.