Did lot of research over the last days to try to understand the potential differences in Reynold tubes and their use on high end Raleigh models in the late 70s.
After reading lots of infos here on BF and on other websites, and after looking at late 70s catalogs/reviews for both the international and French markets, I tried to summarize what was the Reynolds offering in terms of butted tubes, and what tubes Raleigh used for their first two high end models, in particular: the Professional MK V and Competition GS in the US; the Team Pro and the Team Record in France. I used the year 1978 as a sample year for comparison.
Below is a table with Reynolds main butted tubing before and during the 70s, for both international and French markets. In France tubes were imported by M. Dupieux and used a different description as “tenths” of mm, so 5/10e meant .5mm or 24 gauge in SWG. Hence, when it says .8/5, it means .5mm for the thin section and .8mm for the butted section, be it Double Butted or Single Butted, corresponding to a 21/24 gauge. I tried to match and write down both standards for more clarity.
Looking at international catalogs, after using for a while a single combination of .8/5 for TT/ST and .9/6 for the DT, in the early 70s Reynolds made some changes and introduced the 1/7 option. It is my understanding that under the same 531 green decal, Reynolds proposed different gauges, e.g. 1/7 “or” .8/5 (19/22 or 21/24) for the TT and ST. I don’t know what the “or” meant, if frame builders could pick the one they wanted, nor how a bike owner could possibly know which tubes he/she had just looking at the green decal.
In the same years (1972) in France, the same tubes were labeled differently: Light, Extra-Light and Special Super-Light. The two first should correspond to the “or” options above, but gauges were slightly different, while the third option might refer to a legendary .3mm (28) thin section whom (according to a 1970 Le Cycle publication by Daniel Rebour) M. Dupieux claimed he was the exclusive distributor worldwide (and those asking Reynolds to have such tubes were answered they did not exist). Here again, I couldn’t find other decals than those 531 in green, making it hard to identify the exact tube gauges for a bike.
In the second half of the 70s, a distinction appeared between 531 butted tubes (green decal), 531SL (red) and 753. On international catalogs, two options were still available for the standard butted tubes. On French documents, however, just one option was mentioned for standard tubes, and there were slight differences in gauge for the three categories.
Getting back to Raleigh and the 1978 US models, both the Professional MK V and the Competition GS are described as lightweight Reynolds 531 double butted tubes, forks and chainstays with Campagnolo fork ends, with both having the same 531 green decal. So apart from lugs and potential geometry differences (no specs available, but the Pro says “racing geometry and short wheelbase“ while the GS mentions “style and comfort”), there is no way to spot any difference in frame/tubing and we might conclude there’s none. However, it would also be reasonable to think lighter tubes could have been used for the Pro model given the two Reynolds gauge options for the standard green tubes.
As per the French models, both the Team Pro and the Team Record share the same full Reynolds 531 butted tubes green decal and are described as 5/10e. This sole number may refer to the ST, but does not provide any further information. The respective description Extra-Light Reinforced and Light may correspond to different gauges for the standard 531 butted tubes (before the introduction of the 531SL), which would logically make the Pro lighter than the Record. Oddly, however, the third model in the catalog, the Competition, is also said to be full 531 5/10e, but with no mention to lightness, making it harder to position each model in the Reynolds range. To complicate things further, these models, described in French standards, were built in England. So it could simply be that Raleigh mixed tubes to respect a hierarchy, without providing detailed information, none in any case that may have survived.
All this to say the tubing gauge difference question between high end models in the US and France remains unclear and I cannot find any more information to answer that.
It would be very appreciated if the many Reynolds/Raleigh specialists and bike historians here could share their thoughts and provide some clues on this matter. Many thanks!!!
Sources:
https://kuromori.home.blog/reynolds-531/
https://www.kurtkaminer.com/TH_raleigh_cat_78.html
https://forum.tontonvelo.com/viewtopic.php?f=8&t=11755
https://forum.tontonvelo.com/viewtop...=4108&start=45
https://www.bikeforums.net/21466910-post21.html
https://www.engineeringtoolbox.com/s...ge-d_1779.html