In 1958 frame builder Stan Etherden and track coach John Barclay set up Jensen Cycles at 92 Whitehorse Road, Croydon. John had just left coaching the Norwood Paragon whose members were loyal to Stan Butler at Allins Cycles also of Croydon.
Nevertheless Jensen gained a following with other clubs in the area and they also built frames for other bike shops such as Geoffrey Butler under the trade name Croydon Cycle Works. By the mid 1960s they were making around a hundred racing frames per year.
Jensen had difficulties over the name from Jensen Cars who may have threatened legal action but nothing significant seems to have come from it and they continued in business until around 1970.
Concentrating only on top end lightweight scene may have contributed to their demise.
Info courtesy of Classic Lightweights.co.uk