Surely we would be better using some multiple of Pascal (KPa seems to ring a bell somewhere, or is it kPa? I can't remember!). Having come from an industry where a bar was 1kg/cm2 (which is not an official measure of pressure) and kilo was a generic term for all measures!

I pump my tyres so that my thumb doesn't sink in too far when I press and my weight is what it is since the scales gives obviously false figures.

Edit: I can't help thinking that this is getting away from the subject matter of the Audax board and onto the territory of the Knowledge one. Haven't we had some of these arguments before somewhere?

I had to double check, but it turns out I do remember Higher Physics and Engineering correctly:

"A bar (symbol: bar) is a metric unit of pressure that is defined as exactly 100,000 pascals (symbol: Pa). "

I did have to check:

"Reduced to base units in SI, one pascal is one kilogram per meter per second squared"

The pascal is a derived unit, and the bar further derived which was designed for weather forecasting.

Though I do find 40psi easier to remember that 7.75 Bar would 276 Kpa be easier to use?

It's certainly much easier than using the SI unit (N/m^2) which is 275789.79302