Originally Posted by TenGrainBread

Not a lot of 1930s bikes still around...I would pick something newer to chop up, from the 60s or 70s maybe.

Mechanical disc brakes aren't that great. Good centerpull, cantilever, or dual pivot sidepulls are better than most mechanical discs. If you really want disc brakes, hydraulic discs are the only ones really worth the work. But even then they're pretty much unnecessary unless riding in muddy or rough terrain, which a "roadster" would not do.
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