The 'Regens' had been a step forward in Bradford's trolleybus evolution but experience had revealed several weaknesses in the design. A change from regenerative braking to series-dynamic braking with some regeneration improved the relationship between the trolleybus and traction supply system and also enabled the noisy double-reduction final drive to be replaced by a much quieter worm wheel.
634 was built to a Bradford specification and delivered to the Corporation on trial in January 1937. It was an immediate success and led to the placing of an order for 57 trolleybuses with English Electric equipment, although only 42 of these were of the AEC/English Electric combination, the remainder being Weymann-bodied Karriers.
634 went on to give sterling service, its working life of twenty-eight years only just being exceeded by a handful of the later AECs. It was rebodied by East Lancs in 1956, the new bodies being both longer and wider than the originals.
© David Beilby