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1975 BSA B31 For Sale by Auction

  • Petrol
  • 0cc
  • 1975
  • LJT311
  • Multicolour
  • Dealer
  • GB
    Warrington, United Kingdom

Description

National Motorcycle Museum | Solihull, West Midlands Viewing: Tues 21st July from 1pm Auction: Wed 22th July from 10am Location: National Motorcycle Museum, Coventry Road, Bickenhill, Solihull B92 0EJ Registration No: LJT311Frame No: FA71116MOT: Exempt Manufactured and despatched as a 500cc BSA A7 in December 1957 Converted during the 1960s to RGS-style specification with twin carburettors Fitted with a 650cc BSA A10 Gold Star Twin engine and retains original registration ‘LJT 311′ supported by BSA Owners’ Club documentation Introduced in 1946, the BSA A7 was the Birmingham firm’s first post-war parallel twin and quickly established itself as one of Britain’s most popular middleweight motorcycles. Powered by a 500cc twin-cylinder engine and renowned for its reliability, smooth performance and versatility, the A7 formed the basis for a range of sporting and touring models throughout the 1950s. Its robust chassis and adaptable design also made it a favourite amongst owners seeking increased performance, with many benefiting from period upgrades using components from the larger-capacity A10 range. This particular machine is a notably interesting example, retaining its original 1957-dated A7 frame whilst benefiting from a period conversion to 650cc specification. According to accompanying correspondence and documentation from the BSA Owners’ Club, frame number FA7. 1116 was manufactured during 1957 and despatched to The Badger Garages, Blandford Forum, Dorset, on 9th December 1957 as a Grey-finished 500cc A7. Registered as ‘LJT 311’ on 5th February 1958, the machine remains associated with its original registration number. The accompanying history file records that a previous long-term owner purchased the motorcycle in 1963 and retained it until 1974, during which period he converted it into an RGS-style machine and fitted twin carburettors. The machine was subsequently laid up for over 30 years before being reacquired by the same owner in 2018. BSA Owners’ Club dating records confirm that the motorcycle is now fitted with a 650cc A10 Gold Star Twin engine, engine number DA10R. 8452, sourced from a machine originally despatched to California in 1962. The club’s inspection report notes that the machine comprises genuine BSA factory components, with the engine conversion predating the first logbook entry in 1972. Accompanied by its V5C, BSA Owners’ Club correspondence supporting the retention of its original registration number, together with machine dating and registration documentation, this attractive and well-documented A7 represents an appealing opportunity to acquire a characterful BSA twin combining period modifications, known ownership history and the desirable performance benefits of A10 power. ** Bidding will take place live at the venue, online via our H&H website, by telephone and commission - T&Cs apply** Entry by catalogue and can be purchased for £20 (admits 2...

Vehicle location

Cinnamon Park, Cinnamon House, Fearnhead, Warrington, Cheshire, WA4 4SN, United Kingdom
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Advert Details

Category:
Motorcycles
Region:
Cheshire
Reference number:
C2108088
Listed on:
08/07/2026
Model:
BSA B31
Year:
1975
Colour:
Multicolour
Seller type:
Auctioneer

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