I measured the hole-to-hole distance on the 3-arm TA Professional on the 70's Mercier I've just built up for my wife for Larz, and on a Stronglight 3-arm steel cottered crank I recently bougt from Hilary. They are the same. However, rather than a hole which the attaching bolt passes through on an alloy crankarm, the steel crankarm has a smaller threaded hole, which the attaching bolt threads into from behind. Is this a special bolt, or can some common type be used? Also, on the Stronglight rings I lost on eBay, it looks like the outer ring was 6 holes, three used for attaching the crankarms, the other three used for attaching the three-hole inner ring. Anyone familiar with the hardware used to attach alloy rings to cottered steel cranks?
Regards,
Jerry Moos
Jerome & Elizabeth Moos <jerrymoos@sbcglobal.net> wrote: I just lost an eBay auction for a pair of Stronglight alloy chainrings for three arm cranks. I presume these would fit TA Professional, Campy three arm Grand Sport, the Stronglight equivalent, and maybe the Nervar three arm. Mostly, though, I was interested in some rings in useful sizes that would fit the old Stronglight cottered steel cranks.
Can anyone tell me if the alloy rings made for newer (i.e. 70's) alloy three arm cranks will fit the older cottered steel Stronglight and similar cottered steel cranks?
Regards,
Jerry Moos
Houston, TX