"dennis@home" wrote in message
...
On 29/06/2018 08:51, Andy Burns wrote:
Tim Streater wrote:

It can change *shape* but not *length* (except by 1% or so, which no
one is disputing), and that is what I say above.

Now that we know that we're talking about detecting speed changes under
0.5% you can't discount a circumference change of 1%

A flat will change by more than 0.5% as shown empirically by another
poster.

Its also fairly obvious that it will from the destruction of one twin
wheel tyre on a lorry. If it only changed by say 1% the tyre wouldn't
generate enough heat to destroy it and its the heat that does it.

It isnt heat that sees the entire tread come off on a twin wheel tyre,
that is due to the retread coming off.

On single wheels the friction between the slower moving inner bit of the
tyre and the outer will generate plenty of heat and wear to destroy the
tyre.

The twin wheel one won't have this contact so the heat generated in
compressing and stretching the tread is what does it.