They do have something of a clutch spring. It's called a ******er spring (BB-112) on the diagram, a flat band formed into a circular shape that couples the drive clutch and brake expander cone as sort of one unit. This ******er spring holds the two together by friction alone, making sure the drive screw engages both pedaling and braking actions without too much rotational slop. If the ******er spring slips too readily with not enough friction, the drive cone will not move laterally as much as it should, preferring to rotate with the drive cone. The result is excessive rotation when braking and/or engaging forward.
Finding a replacement part may be difficult, as the red band brake has been out of production for decades. Later Bendix models are similar in design, but it's unclear if the parts are interchangeable. If the ******er spring is the culprit, it may be fixable by bending it for a tighter fit over the drive clutch and brake expander. But it does seem like an odd thing to happen. Perhaps the spring is simply burnished and too slippery to function as it should?
Last edited by shecky; 10-31-08 at 11:51 PM.
Reason: Apparently, the forum takes offense at the word "re-tard" (without hyphen).