blackening cad plated bolts

[pmackey]

I am looking for suggestions on blacking factory cad plated bolts on a harley davidson motorcycle

[Rasper]

I would probably throw them in a dish of muriatic acid for a few minutes to get rid of the cadmium and then paint them black.

R

[XK120DHC]

Or you can do it right.. Remove the Cad plating (probably Bright Zinc), replate with the Caswell Zinc/Copy Cad kit then "seal" them with Caswell's Black Chromate (NOT the "Blackener").
You will get the corrosion protection with the zinc and the "look" of the Black Oxide without the rust issues.
The upside to this is, you won't be adding "thickness" to the bolts/nuts like paint will and, it shouldn't chip like paint does.
Back in '68, I built a 110 Cu In "Chopper" (a '39 Knucklehead), took great pains to paint all the nuts and bolts.. after assembly, there wasn't a nut or a bolt that wasn't all chipped up from the sockets and wrenches. Bummer!