On 15/02/2019 09:13, Harry Bloomfield wrote:
I expect the standard traffic car is equipped with just the same system
has our cars have - pulse taken from the ABS of one wheel, then
electronics feeding a stepper motor, except their systems will be set to
display the true speed to ± 1 mph.

Yes. MOST cars today seem to use that system,

IIRC my jaguar speedos were spot on the money +- tyre wear.

In fact it went beyond that as well - the temeperature gauge was always
once warmed up EXACTLY in the dial ceter even when the warning lights
for overheating gearox came on!


I'd question ABS from ONE wheel. More likely a pair to allow for
cornering etc.



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The theory of Communism may be summed up in one sentence: Abolish all
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