Robin Ford 2017

“C’est brutal mais ça marche” Emile Levassor describing his newly invented crash gearbox in the 1890s.

Here’s a brief history of vehicle transmissions. But first the nursery rhyme it is based on:

Oranges and lemons

Oranges and lemons
Say the bells of St Clemons

You owe me five farthings
Say the bells of St Martins

When will you pay me
Say the bells of Old Bailey

When I grow rich
Say the bells of Shoreditch

When will that be
Say the bells of Stepney

I do not know
Says the great bell of Bow

Here is a candle to light you to bed
Here comes a chopper to chop off your head

Transmission history

First into second
As the rev limit beckoned

Don’t mind the clash dears
Said the brutal old crash gears

Gentler is wiser
Said the cone synchroniser

I too thought so
Said the slush-pump auto

I change gears swifter
Said the slick twin-clutch shifter

I disagree
Said the smooth CVT

Here is a headlamp to light up a sign
Here comes a camera to serve you a fine

 Glossary

Transmission history    This is the story of gearboxes, from double-declutching to twin clutches.

Crash gears    The first gearboxes slid gears into and out of mesh – noisily if they weren’t matched for speed (for example by ‘double-declutching’). These crash gearboxes (in modified form) are still used in some heavy trucks; they require fancy coordination of hands and feet.

Cone synchroniser    In synchromesh gearboxes some kind of friction clutch ensures correct matching – often it’s a cone clutch.

Slush-pump    Instead of sliding gears, the classic automatic gearbox has an epicyclic gear train that is controlled by band brakes, (or equivalent), so there is no possibility of crashing noises; a fluid torque converter (slush-pump) usually replaces the clutch found in conventional manual transmissions.

Twin-clutch    The twin clutch system involves swapping the drive between two gear trains – it can give rapid changes.

CVT    A Continuously Variable Transmission or CVT (don’t get me going on our wonderful DAF 44 or more lately our Forester) has no discrete gear ratios at all so speed of changing is not really in question.