Chiltern Railways . The 165/0 units were originally delivered in
Network SouthEast livery for used on routes including fast services from
London Marylebone to
Princes Risborough and
Banbury and local services from
Aylesbury to London and Princes Risborough. In this role they replaced the DMUs. They were later used further afield, when Chiltern services were extended to serve
Leamington Spa,
Warwick,
Solihull and
Birmingham Snow Hill /
Birmingham Moor Street railway station. In December 1993, due to a downturn in traffic as a result of the recession, units 165001-007 were transferred from the Chiltern lines of Network SouthEast to the Thames lines (from Aylesbury to Reading depots). All vehicles had their tripcock equipment removed before transfer. The following year, unit 165007 was returned to the Chiltern lines, followed by 165006 in 1995. Due to unavailability of tripcock equipment upon their return, the units were coupled cab-to-cab and operated for some months between the vehicles of other units as semi-permanently formed four-car units - until tripcock equipment became available, allowing them to be restored to operational two-car units. Following privatisation, two former Chiltern units (165003 and 165005) were repainted into
Thames Trains livery.
Chiltern Railways inherited 34 Class 165/0 units from Network SouthEast, and the remaining five were returned from Thames Trains in 2004 - leaving Chiltern Railways operating the whole subclass. After privatisation they continued to work similar services as before but, with the arrival of the faster
Class 168 Clubman units, the 165
Turbo trains were displaced and are now found less often on expresses to Birmingham, generally working on shorter routes such as stopping services to
Aylesbury,
High Wycombe, and
Stratford-upon-Avon and also the
Birmingham Moor Street -
Leamington Spa local services. A new depot was built at Aylesbury in 1990/1991 for the maintenance of these trains and has been enlarged since British Rail days, with the addition of a wheel lathe. Light maintenance and refuelling is carried out at Wembley LMD and
Tyseley TMD, and units can occasionally be found at
Stourbridge LMD. Units are also regularly stabled in the Marylebone station environs, Aylesbury South Sidings and at Banbury, where a further depot is currently under construction at the south end of the station on the western side of the line. All Chiltern units were refurbished between late 2003 and early 2005. • seats re-trimmed • interiors repainted • Passenger Information Displays replaced with a GPS-based system • upgraded lavatory facilities • flooring stripped and replaced In 2012, First Great Western took delivery of Class 180
Adelante units for
Cotswold Line services, and three-car
Sprinter units for
Reading to Basingstoke Line services, allowing Class 165 and 166 units to be used to reinforce Thames Valley services. In late 2015, as part of the rebranding to GWR, the Class 165 fleet had all first-class sections removed to increase capacity. Following the electrification of the
Great Western Main Line up to Didcot Parkway, as well as the
Reading-Taunton line as far as Newbury, services between London Paddington and Didcot Parkway, as well as between Reading and Newbury, have been operated by new
Class 387 electric multiple units, allowing much of the existing Class 165 fleet to move to the Bristol area. Class 165s continue to service the aforementioned branch lines, but no longer run to London Paddington except during peak hours.
Bristol area Following the transfer of the 166 units to
St Philip's Marsh depot in July 2017, some of the 165 services have since followed on with the first 165 operating in the Bristol area in July 2018. Since then and alongside the 166s, they have rapidly been introduced on other services such as the
Weston-super-Mare to
Filton Abbey Wood (now
Weston-super-Mare /
Bristol Temple Meads to
Severn Beach /
Filton Abbey Wood) services, the
Cardiff Central to
Taunton services, the
Golden Valley Line, the
Heart of Wessex Line and also some services on the
Wessex Main Line as far as
Warminster and
Southampton Central. In January 2019, they began operating the regional service between
Cardiff Central and
Portsmouth Harbour which allowed more of the
Class 158 units that solely operated this service to move more west. The transfer of the 165 (and 166) units to services in and around
Bristol and
Exeter have overall allowed units that previously operated these services to move further west, such as the
Class 150 and Class 158 units. More so than the 166 units, a lot of the 165 units remain to be based at
Reading TMD where they continue to operate Thames Valley services. ==Fleet details==