I was trawling through a folder where I put images I intend to blog about when I rediscovered this series I took last December of a 1979 Columbia Trans Am that was locked to a railing somewhere along Newbury Street in Boston.
What initially caught my eye was the shopping bag seat cover and "Deluxe decorated chainwheel cover":
Casting my eyes forward, I beheld the awesome fork rake...
... and funky handlebars but then I noticed the truly unique feature of this bike...
... Shimano Positron shifting! According to the late, great Sheldon Brown, Positron was Shimano's first attempt at indexed shifting. Back then, they thought that expert cyclists already knew how to shift and so they targeted Positron shifting at entry level riders.
The plan backfired for two reasons: 1) since it was aimed at inexpensive bikes, the system had to be so cheaply made that it was not very reliable 2) this also meant that indexed shifting got tainted with the "beginner" label, slowing adoption of better made systems by experienced cyclists.
The bike looked completely stock as far as I can tell, who knows if those are the original tires. Here's a page from the 1982 Shimano catalog (click here to browse the whole thing):
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| (click to see 1982 Shimano Catalog at Sheldon Brown's website) |
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| (click to see the Columbia timeline at Mr. Columbia's website) |
