| British Rail Class 201 | |
|---|---|
 1004 at London Cannon Street in 1984 | |
| In service | 1957–1986 |
| Manufacturer | Eastleigh and Ashford Works |
| Number built | 42 vehicles (7 units) |
| Number preserved | 1 unit |
| Formation | DMBSO-TSOL-TSOL-TFK-TSOL-DMBSO |
| Operators | Southern Region of British Railways |
| Specifications | |
| Car body construction | Steel |
| Car length | 17.67 m (58 ft 0 in) |
| Width | 2.74 m (9 ft 0 in) |
| Height | 3.82 m (12 ft 6 in) |
| Doors | Hinged slam (now centrally locked) |
| Maximum speed | 75 mph (121 km/h) |
| Weight | 55 long tons (56 t; 62 short tons) |
| Traction system | DEMU |
| Prime mover(s) | English Electric 4SRKT Mark II, 2 per set |
| Traction motors | English-Electric EE507 traction motors, 4 per set |
| Power output | 1,000 hp (750 kW) |
| Bogies | BR Standard. ExEMU coaches Commonwealth or B5 |
| Braking system(s) | Air/EP |
| Coupling system | Drop-head buck-eye[1] |
| Multiple working | with Classes 201 to 207 |
| Track gauge | 1,435 mm (4 ft 8+1⁄2 in) standard gauge |
The British Rail Class 201 (or 6S) six-car diesel-electric multiple units (DEMUs) were built in 1957–1958 at Eastleigh and underframes were built at Ashford.
The Southern Region Class 201-207 DEMUs are nicknamed 'Thumpers' due to the noise they made while in motion, owing to the four cylinder engines.[2][3]
These units were built for the London-Hastings line, with a narrow body profile to accommodate the restricted tunnel loading gauge on that line.
- ^ Marsden, Colin (2011). Traction Recognition. Hersham: Ian Allan Publishing Ltd. p. 162. ISBN 978-0-7110-3494-5.
- ^ "Preserved Thumpers". www.preservedthumpers.com. Archived from the original on 19 August 2014.
- ^ "Multiple Units". www.eorailway.co.uk. Archived from the original on 13 November 2017.