Originally Posted by cdelong
100% sure your problem is that the brake pulley or brake hub is worn. Take the shaft out and remove the pulley/hub assembly. The pulley will be loose on the hub.
Now you just have to figure out which one is worn. It could be the pulley or hub. If a new pulley is tight on the hub then you are all set. If a new pulley is loose, then you need a hub.
In a pinch I've wrapped teflon or electrical tape on the hub before I put the pulley back on.
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