I have two "Baby" Gran Sports of only 150 mm cranksize and one Gran Sport of 170 mm. All three-arm and 116 mm bcd, bought NOS but said to be from 1976.
From 1976 I have also a 170 mm NR with five-arm 144 mm bcd - very standard - and from 1982 a Gran Sport same size five-arm. A SR bought NOS somewhat later is very similar to the NR but a tad more slender, the NR is in its turn slightly more tender than the full lenght GSs that are also more square and have wider and more shallow groves. The baby sports are more slender than the 170 mm ones.
I´ve seen one three-ring NR from the early 80´s (I hope before 1983 so that it´s not OT) that used a 36t inner ring of 116 mm bcd on five crank arms that were not only bored but had a different shape - different grove and less tapering cranks than normal NR.
Chuck?
fwiw
Olof Stroh Uppsala Sweden
> > Anybody else have 144mm and/or 116mm sets
> > handy that they could examine?
> One final note: my recollection is that the bolt spacing
> on the 116mm bcd cranks was not symetrical. That is, they're
> not separated by a constant 72 degree interval. Do I remember
> correctly?
> Regards,
> Fred Rednor - Arlington, Virginia
>
>
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