# Why kms?

#### RichardB

##### Slightly retro
I buy fuel in litres but convert this to gallons to calculate fuel consumption in mpg. Mpl seems just wrong and litres per 100km also involves converting one of the metrics between imperial and metric (I felt it was necessary to insert a link explaining the difference between a metric and the metric measurement system..... sorry). Once distance is measured in km and fuel in litres then a natural adoption of the ltr/100km will be inevitable.
"Divide by 4.54608, easy."
"Nerd."

I think it's the only conversion factor I know to 5 decimal places.

And litres per 100 km is just wrong, because a good number is a low number, whereas any fule kno that with fuel consumption a good number is a high number.

I'm semi-serious. These things are completely ingrained, and exist in a part of the brain that is very resistant to change.

#### biggs682

##### Smile a mile bike provider
KM's are higher so looks better but i use miles

#### Tribansman

##### Senior Member
I definitely think in miles and on the rare occasions I've tried to use km - on long audaxes mainly, as distances between controls, etc are stated in km and it's easier to split 1200km into chunks than 745 miles - I am mentally converting them back into miles to be able to properly visualise the distance.

So as you kind of suggested @I like Skol guess it's about what's intuitive / we think in, as it is for speaking other languages. I'd probably only start thinking in kms if I moved to somewhere where that was the common currency so was immersed in it and 'how long a km is' became hard wired in

#### figbat

##### Slippery scientist
Funny thing about buying liquids isn't it. Milk and beer still commonly traded in pints while nearly all other consumable liquids are sold in millilitres or litres.
[...]
The pint is an oddity, but the mile is still the official unit. If pubs stopped selling beer in pints and changed to half and quarter litres I bet 'the pint' as a unit of liquid would quite rapidly fall out of use.
The Weights and Measures Act still allows for beer and milk to be sold in pints, so it is still an “official” unit. Pretty much all other items must be sold in metric, by law.