"dennis@home" wrote in message
...
On 01/07/2018 07:01, Jeff wrote:


"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.

Well why do you think it comes off?

Because trucks still use retreads.

Anyway quite often its the entire carcass too.

Hardly ever.

If you have driven million miles on motorways you tend to see a lot of
this stuff.

Hardly ever the entire carcass.