Thanks for taking the time to share this information with the folks on CR List. I purchased a Mercian King of Mercia Racing Model in the mid '80's and with the exception of my specification error, it would pass for a '60's or '70's bike. The people at Mercian were very accommodating. I have a beautiful paint scheme (good), Nervex Lugs (good) lots of chrome (good) BUT I specified the three(3) cable guides on the top tube(bad). I also specified longer chain stays which was also good. I should have, however asked for cable stops to be brazed on the lower portion of the top tube similar to the older bikes. In my defense, I was not trying to spec a classic bike, but rather what I thought was a good design. My brother also has a Mercian and his bike is very nice but a little more modern than mine. I would not hesitate to recommend Mercian to anyone on the CR List, as these bikes are made as they were then. I have been working on the funding for a Vincitore Model. Bob Jackson also offers to build framesets that are truly classic in design as well.
A bidder on my e-bay site asked what bikes we still find on the road in the UK. In the last few weeks I have come across quite a few examples of 50s and 60s bikes in common use. Names like Bates, Paris, Hetchins, Flying Scott, Rotrax, Bob Jackson, Claud Butler, Freddie Grubb, Ellis Briggs, Langsett, Whitcomb, Shorter, Roberts, Condor and Mercian still crop up regularly amongst club cyclists. Most of these are on the excellent Classic Rendezvous British Site and do occasionally appear in classified ads - particularly in my neck of the woods. If you're looking for something in particular, don't be afraid to ask and I'll keep my eyes open. Beware, though - our locals do tend to know a Flying Gate from a Magnum Opus!
Of these, I always feel that Claud Butler and Freddie Grubb are problem areas for collectors as even back then I remember there was confusion between the original hand-builts and the mass-produced bikes made by the Holdsworthy Company from about '60 onwards, so beware. Find someone who can date them if you're offered one.
As a young boy in that era, I aspired to having a racer like a Carlton, Dawes, and my particular favourite - the Viking Severn Valley. The trouble was that once you actually got into racing, these ceased to be the bees-knees and you ended up having to invest in one of the bespoke frames like the ones in the above list. I can't remember all the bikes that have passed through my hands, but they have included several Mercians and Bob Jacksons, an old Hetchins, a Shorter, a Harry Quinn and an old Claud Butler trackbike.
As far as good guides to the parts that were available, if you ever come across either a copy of Bike Rider's Aids (The title was Kosher in the 60s!) produced by the Holdsworthy Company every year or a copy of an old Ron Kitching catalogue, then snap it up. I have a feeling that Hilary Stone put one up for sale recently. I still have ones from most years in the 60s and wouldn't part with them for anything.
What advice would I give to a potential collector of Bit bikes? Well, ignoring something like a top-end Hetchins - I would go for a Bob Jackson or a Mercian. They are true to the spirit of the British handbuilt - both firms have at times made frames with lugwork as good as anything you'll find in the more sought after makes and of course the big advantage is that they are still around so a full re-enamel with the right decals is no problem.