Harry Quinn Cycles was essentially a Liverpool business, although the concern had various locations. For instance, in the mid-1980s, they were on the Ivy Tower Farm, at St Florence, near Tenby Pembrokeshire, Wales.
          Harry Quinn Cycles began as Coronet Cycles in 1890s. Harry himself was the son of the founder, also Harry, and was then joined by his own son, Peter. The 'Harry Quinn' marque was begun in the 1950s. The racing bikes were noted for their short wheelbase and steep angles, relative to other contemporaneous makes. Harry also served as the bike designer for others, including Viking cycles & Falcon.
          Harry passed away on 1st October 2010, aged 93. 

"Ultra Light Road Machine"
Article with specs in Cycling magazine, July 24, 1963

Gordon Singleton of Canada wins Pan Am Gold on his Harry Quinn

Matthew Van-den-Heuvel 's Q3703

Donal Turner's # Q4475

Dave Stoke's Q5065

Kerrin Lyons' #A0155

Harry Quinn 753 road frame serial #Q113  (Early 1980s?)

Carl Wallace's # Q136
1988? "Custom built for an Abergavenny RC rider
when Harry Quinn was living in Tenby, Wales"

Bob Evans Q268

Roy Clarks #Q804

In 1988, Graham Coulson built his own Harry Quinn #9014
under the guidance of father & son, Peter & Harry Quinn.

 #Q1020 made in 1991 for Pro rider Colin Sturgess and raced at the 91 world uci track championships in Stuttgart to a bronze medal in the individual pursuit and also a world record time.
Picture courtesy Matthew Van-den-Heuvel

1988 -John Shore also attended the Quinn frame 
building school, and with Harry & Peter, built his  #9015

"Harry Quinn" bikes not made in Quinn workshops....
Apparently in the 1980s and on, various attempts were made to cash in on
the brand name by having HQ bikes made in Ireland, in England and abroad...

Keith Thomas' Quinn which looks as if it may
have been produced to order by an outside vendor.

Japanese (?) manufactured Harry Quinn bicycle of more modest features
(images from eBay auction, Aug 2009)