Re: Campy Gran Sport Crank w/chainguard - Triple it ?



D

Donald Gillies

Guest
Retroed Bob <[email protected]> writes:

>I've run across a 3 arm Campy Grand Sport Crankset, I think from the
>late 70's. It has a chrome chainguard as an outer ring. It appears
>that the outer ring and chainguard attache directly to the arm whereas
>the inner ring looks like it attaches to the outer ring with a larger
>BCD


>Questions:


>- Any idea if I could pull the chainguard from this and install
>another outer ring and make it a triple ? Or is the guard just thin
>metal and not full thickness?


>- Any idea of the BCD for the inner and outer rings ? Does it match
>the TA 3 arm stuff of the era ? What about the inner ring BCD ?


Come on, a few seconds with a millimeter ruler should tell you the
bcd.

This version of campy gran sport is the least desired gran sport that
Campagnolo ever made. It is not really considered "classic
equipment". There are alternative choices that are more desirable,
e.g. :

a. Campy made a gransport in the late 70's / early 1980's that was
just like nuovo record with slightly straighter spider arms and
simpler milling of the crank arms. It's standard 144 bcd, aluminum,
rings still available from TA new and other NOS. It might be better
to upgrade to this gran sport.

b. Then, campy made victory & triomphe in 1984/5, a 116 bcd
chainring. Since it was 116 bcd it was easy to triplize
(www.biketoolsetc.com for triple-chainring bolts) and these cranks are
cheap. For example, I bought one used on ebay for $10 and got an
inner 36T ring from wwcyclery on ebay for another $10, they go down to
34T - bicycle classics have 35T chainrings.

- Don Gillies
San Diego