Butted Forks and Stays - Is there a real advantage?
#26
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Are we mixing eras here? I see several examples of butted fork blades and stays but they all seem to be from more modern tubesets. Is T-Mar correct about the tubesets from the classic period? I'm assuming that would be SL, 531, and other contemporary tubesets of the 60s and 70s.
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1959 Bottecchia Milano-Sanremo(frame), 1966 Bottecchia Professional (frame), 1971 Bottecchia Professional (frame),
1973 Bottecchia Gran Turismo, 1974 Bottecchia Special, 1977 Bottecchia Special (frame),
1974 Peugeot UO-8, 1988 Panasonic PT-3500, 2002 Bianchi Veloce, 2004 Bianchi Pista
1959 Bottecchia Milano-Sanremo(frame), 1966 Bottecchia Professional (frame), 1971 Bottecchia Professional (frame),
1973 Bottecchia Gran Turismo, 1974 Bottecchia Special, 1977 Bottecchia Special (frame),
1974 Peugeot UO-8, 1988 Panasonic PT-3500, 2002 Bianchi Veloce, 2004 Bianchi Pista
#27
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pretty sure Reynolds and Columbus were using butted stays and fork blades back in the classic period too. It would make no sense for them not to have done so. In general, the difference between today's tubing and earlier tubing is higher strength and heat treating which leads to generally thinner tubes.
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Related question: my 1983 Trek 600 has 531db main tubes, but the catalog only specifies "manganese alloy" for forks and stays....anyone know who made the tubes? 1982, similar model, shows Ishiwata Manganese Alloy for those components. I couldn't find Ishiwata manganese alloy in the Ishiwata catalog on the equus site.....
Thanks, Mark
ps. Should have named this thread "Everything you ever wanted to know about stays and forks but were afraid to ask"!
Thanks, Mark
ps. Should have named this thread "Everything you ever wanted to know about stays and forks but were afraid to ask"!
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72 Frejus (for sale), Holdsworth Record (for sale) & special CNC / 74 Italvega NR (for sale) / c80 ?French? / 82 Raleigh Intl MkII (for sale)/ 83 Trek 620 (for sale)/ 84 Bruce Gordon Chinook (for sale)/ 85 Ron Cooper / 87 Centurion IM MV (for sale) / 03 Casati Dardo / 08 BF IRO / 09 Dogma FPX / 10 Vassago Fisticuff
72 Frejus (for sale), Holdsworth Record (for sale) & special CNC / 74 Italvega NR (for sale) / c80 ?French? / 82 Raleigh Intl MkII (for sale)/ 83 Trek 620 (for sale)/ 84 Bruce Gordon Chinook (for sale)/ 85 Ron Cooper / 87 Centurion IM MV (for sale) / 03 Casati Dardo / 08 BF IRO / 09 Dogma FPX / 10 Vassago Fisticuff
#29
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While I have nowhere near the experience of JohnDThompson with raw tubes, my observations do echo his, that the internal taper on Reynolds blades was meant to offset the progressive thickening towards the dropout end that occurred as the tube underwent the external tapering process. The end result is a blade with basically constant thickness. Any mention of the varying wall thickness/tubing gauges for the blades in Reynolds literature appears to be a reference to the dimensions prior to external tapering, and was simply a case of marketing, to make their tubesets appear technologically superior to the competition.
I stand by my original comment. This is a C&V thread, so my statement was qualified by stating that it applied to vintage tubesets. As suggested by Kommissar 89, the cited examples of butted stays and/or forks are modern tubesets, less than 20 years old.
During the vintage era there were some examples of trying to increase the strength and rigidity of stays and forks though it was not by butting. Besides Reynolds taper gauge forks, the most notable example was the use of helical splines as employed by Columbus in their SLX and SPX tubesets, later to followed by Miyata's STB sets and other examples. Even these sets did not arrive until the mid 1980s. At the very tail end of the vintage era we start to see other methods. The adoption of TIG welding permitted the use of oversize tubes and the discretionary shaping of these and other tubes, as designers tried to achieve their optimum balance of strength, rigidity. weight and resilience.
Beyond what was offered to them by the tube companies, vintage framebuilders had their own method to beef things up. Internal sleeves or wood plugs were often added to the top end of fork blades or the bottom bracket end of chainstays. And then there was the chainstay bridge, a standard item that started to disappear after the introduction of splined tubesets and investment cast bottom bracket shells. Similarly, thinner gauge fork blades typically had stiffening tangs added to the inside of the blades, at the crown end, until the adoption of fully sloping, investment cast crowns with internal tangs.
If we look hard enough, there may be some example of a visionary offering a butted stay or fork prior to 1989, but offhand I'm not aware. During the vintage era, butting, to the best of my knowledge, was applied only to the 3 main tubes (and steerer tube).
I stand by my original comment. This is a C&V thread, so my statement was qualified by stating that it applied to vintage tubesets. As suggested by Kommissar 89, the cited examples of butted stays and/or forks are modern tubesets, less than 20 years old.
During the vintage era there were some examples of trying to increase the strength and rigidity of stays and forks though it was not by butting. Besides Reynolds taper gauge forks, the most notable example was the use of helical splines as employed by Columbus in their SLX and SPX tubesets, later to followed by Miyata's STB sets and other examples. Even these sets did not arrive until the mid 1980s. At the very tail end of the vintage era we start to see other methods. The adoption of TIG welding permitted the use of oversize tubes and the discretionary shaping of these and other tubes, as designers tried to achieve their optimum balance of strength, rigidity. weight and resilience.
Beyond what was offered to them by the tube companies, vintage framebuilders had their own method to beef things up. Internal sleeves or wood plugs were often added to the top end of fork blades or the bottom bracket end of chainstays. And then there was the chainstay bridge, a standard item that started to disappear after the introduction of splined tubesets and investment cast bottom bracket shells. Similarly, thinner gauge fork blades typically had stiffening tangs added to the inside of the blades, at the crown end, until the adoption of fully sloping, investment cast crowns with internal tangs.
If we look hard enough, there may be some example of a visionary offering a butted stay or fork prior to 1989, but offhand I'm not aware. During the vintage era, butting, to the best of my knowledge, was applied only to the 3 main tubes (and steerer tube).
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