Where would BBC Radio 4 be without ‘The Archers’ it’s decades long running saga of rural life? Who cares? I’m talking about Sturmey Archer gearboxes…. You see, I’ve only realised the value of the humble gearbox since running up and down the road trying to start my single speed Blackburne ‘Scarlet Runner’ Brooklands racer replica. Thing is, veteran era single-speed race bikes have no clutch or kickstart. To get them going you had either to pedal them or run alongside…