Hillary,
"British builders far more often used 0.6/0.9 531"
From what I've seen I agree...
To clarify what I said:
"Many production bikes built from the early 70s through the early 80s used Reynolds 531 7/10 wall thickness tubing."
I'm talking about the larger bike manufacturers such as the French companies, Motobecane, Peugeot, Gitane and others, plus Raleigh, and probably Dawes, Falcon, Holdsworth and so on. Same thing with Columbus SP and Italian manufacturers from that era.
In reference to Raleigh, it seems during the Bike Boom era that they used whatever was on the shelf or maybe what Reynolds had left over. :-)
A large number of bikes built in the UK were made by smaller builders and they most likely used lighter gage tubing. They were not "production models" in the sense that there weren't hundreds of identical frames made at the same time.
By the late 70s and early 80s many if not most Italian builders were using Columbus SL vs SP tubing where appropriate for the frame size and style. Same thing in France where the lighter gauges of Super Vitus and/or Columbus SL tubing became popular.
Advertised weights for tubing sets have to be taken with a gain of salt because the various makers offered different length tubes in their sets plus different diameter seat stays and so on. French made Durifort, Vitus and Super Vitus sets were listed sans head tubes and steerers.
I did post mortems on a lot of crashed frames during the 1970s plus I've seen repairs in progress by several frame builders. I was surprised by what I found!
The bikes we cover on this list were for the most part "Hand Crafted".
They're not sacred objects! They were built as bicycles not Swiss watch movements and as such flaws and building shortcuts should not necessarily be looked down on as long as they did what they were intended to do and not fail prematurely.
Hand Crafted is the operant term here. ;-)
The beauty and sometimes crudeness of a hand crafted article is what appeals to me.
BTW, I've seen as many flaws in Swiss built bikes as in say French ones! ;-)
Chas. Colerich Oakland, CA USA
Hilary Stone wrote:
> British builders far more often used 0.6/0.9 531 (which is sometimes
> described by Reynolds as 0.55/0.9) - except on the largest frames -
> 23.5in and larger. 0.7/1.0 is quite rare on British built 531 frames
> from all periods...
>
> Hilary Stone, Bristol, British Isles