wow, zombie thread or what?
IIRC there are two sizes of tool, one for the standard weinmann brakes, and a slightly larger one for the posher ('Carrera'/405/605 etc) model brakes. Only later models of weinmann brakes use such a tool at all; earlier versions of the brake had a pair of locknuts on the centrebolt with no cover; much simpler (and IMHO better looking).
FWIW if you want to centre such weinmann side pulls, and you don't have the tool, you can....
a) do what cycle mechanics do, which is to use a drift and to tap one of the spring loops down; the caliper moves round provided the centre bolt isn't super tight, or
b) use a small hexagon socket of the correct size, or
c) pop the plastic cap off, and use a spanner on the locknuts beneath to hold the brake centred.
IME these brakes stay reasonably well centred better if the springs are lubricated where they bear against the arms.
Some folk are happy to cast these brakes into the dustbin of history with nary a thought. Especially with longer reach arms, they were often not very good brakes, 'tis true. But at the time they were at least as good as other brakes of similar cost, and for several years the lightest brakeset on the market was the weinmann 500, all without using Ti parts.
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