Originally Posted by juvela

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chainset -

someone has replaced the stock 16mm fixing bolts with the one-key release mechanism

in the Zeus design the removal thread is the standard 22.0mm and the fixing bolt head is 16mm
this means a standard 16mm socket or spanner will have a too thick wall to fit so one needs a special tool or a thinwall socket

the one-key release is convenient for the cycle owner but has the double-edged trait of making it possible for a thief to silently remove the machine's chainset and pedals in about ten seconds

while the chainset has a familiar looking five-pin pattern it is unique - not the standard 50.4mm BCD - interchanging with nothing else

since it has been out of production for over a half century replacement chainwheels are somewhat thin on the ground; at OEM use the standard offering was a dentition of 45-52 for the chainset so the few chainwheels which may come up are nearly all one of those two sizes

the BCD for the inner chainwheel is the old Campag one of 151mm with the smallest chainwheel produced being 43T

pedals -

the HKS brand for pedals is a new one for me

checked at VB and at the Speedplay Museum and there are no entries for this brand

tried enlarging photo but was unable to make out clearly any of the markings

the only Spanish pedal brands am familiar with other than Zeus/Alfa are Iberia, Notario & Olimpic

stem -

have never known the producer for the Cinelli 1A replica stems found on some of the Zeus cycles of this time
they are completely without marks as recalled

one possible manufacturer might be AKRONT


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