At 11:36 AM -0700 4/22/07, Chuck Schmidt wrote:
>Explain the amount tread/Q factor has grown and shrunk over the last
>one hundred years. Let's see some numbers to go along with a lone
>quote from 1962. It would make for a great article in VBQ don't you
>think?
We are working on it. When I was in Europe, I measured geometries, tread and other specs of a large number of bikes from the 1880s until recently.
Tread was a major concern in the 1940s and 1950s. Looking over my notes, I found that Ernest Csuka, the owner of Cycles Alex Singer, told me that racers always wanted their frame optimized so they could use a BB spindle that was just a tad shorter than usual, thus bringing their pedals closer together.
That is why many older frames have indentations in the right chainstay to clear the small chainring. If tread was of no concern, it would have been easier simply to use a longer BB spindle.
It is noteworthy that Campagnolo specifically states that the tread of their latest OT carbon cranks with integrated bottom bracket is no wider than that of their previous models - 146 mm. They seem to think it still is important to some European racers...
Jan Heine
Editor
Bicycle Quarterly
140 Lakeside Ave #C
Seattle WA 98122
http://www.bikequarterly.com