Hilary -
Could you tell me what you suspect was used on a 25-inch Comp GS, 1978? Might the gauge vary by tube: main frame vs. stays vs fork blades?
thank you
Damien Roohr
Canton, CT
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
Jon Spangler wrote:
> Charles,
>
> I am absolutely certain that Reynolds 531 7/10 gauge tubing is lighter than Columbus SP tubing in 7/10 gauge.
> Forever. No matter what the scales read. Because God made Reynolds tubing and the Devil made Columbus...
>
> Jon Spangler
> a metric Reynolds partisan to the death in Alameda, CA USA :-)
>
>
>
> Message: 12
> Date: Mon, 19 Apr 2010 01:42:31 -0700
> From: verktyg <verktyg@aol.com>
> Subject: Re: [CR] Falcon Professional
> To: Bill Roberts <bill.roberts@earthlink.net>,
> Classicrendezvous@bikelist.org
> Message-ID: <4BCC1777.7050109@aol.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> Another point that I mentioned before, there was always an urban bicycle
> myth that Reynolds 531 tubing was lighter than Columbus (SP) tubing.
>
> Many production bikes built from the early 70s through the early 80s
> used Reynolds 531 7/10 wall thickness tubing.
>
> That's the same 7/10 wall thickness as Columbus SP tubing!
>
> The links below show some pages from the 1980 Gitane catalog for their
> top of the line Olympic model. The spec sheet is in French but you can
> see the 7/10 reference:
>
> http://tinyurl.com/
> http://tinyurl.com/
>
>
> What I've heard over the years was that back in the day a pro racer only
> had 1 or 2 bikes for the whole season; they were usually made out of
> heavier gage tubing to survive crashes and handling abuse between stages.
>
> Another factor, an economic one, I suspect that many bike manufactures
> used heavier gage tubing in their production bikes because they could
> employ less skilled workers to braze up the frames thus work faster.
> Also these frames were less likely to get dented during the
> manufacturing process.
>
> Chas. Colerich
> Oakland, CA USA
>
> Bill Roberts wrote:
>> Interesting post Chas, thanks.
>>
>> Regarding it being a somewhat common build trick to use the thicker wall
>> Reynolds 531 seat tubes in 70's English bikes. Many 70's Ron Coopers indeed
>> seem to be this way (27.0 post), in sizes 58c and larger. Versus a 27.2 in
>> 57c and below. Sheldon Brown agreed this was intentional (tubing
>> selection). I've noticed this on several of Ron's frames. With Ron being
>> very meticulous in both design and execution, I expect it is intentional,
>> and the thicker tube was used.
>>
>>
>> Bill Roberts
>> Jacksonville, Oregon USA
>
> Jon Spangler
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