You don't have an all drum M/C do you? I'm wondering if there is a residual pressure valve in the rear portion of the M/C. This is an MC for a GM truck with the same brake system as me (2.6-2.7" front caliper pistons, same caliper type, and 15/16" rear wheel cylinders). I have a separate small residual valve in the rear circuit for the drums.
1967 Dodge Coronet Deluxe station wagon
1.03" T-bars, QA1 arms/rods, Cordoba/GM Metric/Volare brake & knuckle, XHDs, Hellwig rear sway, 318 Magnum w/ air gap, 727, 3.23s
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