The line between "there is life left" and "it is finished" is sharper than it looks. There are three separate criteria and each says something different: depth, distribution and age.
1. Depth: the legal limit is 1.6 mm
The legal minimum tread depth is 1.6 mm. A tyre that reaches it must be replaced.
Small raised bars are moulded into the grooves at exactly that depth — the TWI (tread wear indicator). When the tread surface is level with those bars, the tyre has reached the limit. Small marks on the sidewall show where to find them.
Do not take the measurement at a single point: a tread does not wear at the same rate everywhere.
2. Distribution: where the wear is concentrated
This second criterion gets far less attention than depth, and it is the one that carries the most information.
- Worn in the centre, shoulders still fresh — mostly straight roads and motorway use. High pressure accelerates it.
- Worn at the shoulders, centre still fresh — corner-heavy use. Low pressure contributes too.
- Marked wear on one side only — may relate to road camber or to fitting.
- A stepped or sawtooth appearance — usually the sign of a balance or fitting problem.
⚠️ These are signs, not diagnoses. We cannot tell you the cause without seeing your motorcycle. If you find either of the last two, show it to your authorised dealer; the cause may lie somewhere other than the tyre, in which case fitting a new one will not solve it, only repeat it.
3. Age: the DOT code
The last four digits of the DOT code on the sidewall give the week and year of manufacture. For example 2325 — the 23rd week of 2025.
Rubber ages even when unused. A tyre with plenty of tread left can still be old; on machines that are ridden little, parked for long periods or kept outdoors, this is the criterion that matters.
⚠️ We are not giving a "replace after this many years" figure — that threshold varies between manufacturers. We are telling you what the code says; if your tyre is old, have your dealer look at it.
What must be replaced regardless of tread depth
The following are not a "can it still be used" discussion:
- A bulge or blister in the sidewall — this means structural damage
- Any cut or tear where the carcass cord is visible
- Deep cuts, splits and deep cracking
- A repair made in the sidewall
The warranty side
Our statutory warranty runs for 2 years or 1.6 mm of tread depth — whichever comes first. So reaching the tread limit is not only a safety threshold; it is also the point at which the warranty period ends.
Our Technical Information page carries the short version of these criteria.