From Graces Guide
Coventry Bicycles of Osborne Road, then Wellington Street, Coventry.
Also traded as Coventry Motor Cycle Co
1923 Coventry B and S were motorcycles produced in 1923 by Coventry Bicycles
1923-5 Coventry B and D were motorcycles produced from 1923 to 1925 by Barbury and Downes of Coventry Bicycles
1924 The Wee MacGregor or Wee Mac motorcycle was made at the Coventry Motor Cycle Co of Wellington Street, Coventry by Barbury and Downes, former employees of the Hobart Motor Cycle Co.
At some point the name Coventry Bicycles was established for the business run by Barbury and Downes
1931 They introduced the 'Three Spires' motorcycle
1936 Company name changed to Associated Cycle Manufacturers of Coventry
1938 Production moved to the old Triumph factory in Priory Street 
Coventry B and D were motorcycles produced from 1923 to 1925 by Barbury and Downes of Coventry Bicycles.
Although the marque was short lived, the partners produced a wide range of capacity classes. They also produced some models sold under the name styles of others, including the little 179cc two-stroke Wee MacGregor. Their own models were mainly four-strokes powered by JAP engines ranging from 346cc to 976cc. For a while the 348cc Barr and Stroud sleeve-valve engine was sold under the Coventry B and S brand name.
Coventry B and S were motorcycles produced in 1923 by Coventry Bicycles
The initials B and S signified the fitting of Barr and Stroud engines. These were 349cc sleeve-valve singles, driving through a three-speed Burman gearbox and chain to the rear wheel. They also produced at least one machine with the so-called Octopus B and S engine, with two inlet and four exhaust stubs. This was an attempt to improve breathing and exhausting.
The parent company did continue into 1924, by which time the models were badged with the Coventry B and D transfer.
Three Spires was a motorcycle produced between 1931 and 1932, by Coventry Bicycles.
Their machine was a lightweight fitted with a 147cc Villiers engine, two-speed Albion gearbox and a basic set of cycle parts. Its style was more suited to that of the previous decade and it was not on the market for long.
Wee MacGregor were motorcycles produced from 1922 to 1924, by the Coventry Motor Cycle Co. It was a sub-marque of Coventry Bicycles, builders of the Coventry B and D.
The first examples had 170cc two-stroke Hobart engines and either plain two-speed or two-speed with clutch, kick-start transmissions and belt final-drive.
Later, the engine capacity was increased to 205cc and an open-framed ladies' model could be obtained.
Sources of Information
- The British Motorcycle Directory - Over 1,100 Marques from 1888 - by Roy Bacon and Ken Hallworth. Pub: The Crowood Press 2004 ISBN 1 86126 674 X
- The Encyclopedia of the Motorcycle by Peter Henshaw. Published 2007. ISBN 978 1 8401 3967 9