foxtrapper wrote: Interesting. I've never had drum brakes roar, and in googling it I find only a few clear complaints of it, and not a single fix. So, using my vague musical and engineering background, I'm going to say you've got to get some vibration going to get a roar. The only area to get vibration from is rubbing surfaces, and the only ones you've got are the brake shoes and the drum itself. So, if it were my brakes: I'd make sure the brake shoes ride smoothly and with light lubrication on the backing plate. This would eliminate backing plate resonance. I'd file the leading and trailing edges of the brake shoe lining. It could help reduce vibration between the shoes and drum. I'd hold the pads against the drum to see if they match radius. Looking especially for gap in the center, with the leading and trailing sections of the lining contacting only. I'd consider adjusting them with my belt sander if necessary. Air gaps can create some wicked resonance that could lead to brake drum ringing. I'd consider how to zip-tie / wire-tie some sort of damper ring onto the outside of the brake drum. Just like damping a trumpet bell.
I like how you think. I'm a musician as well. I thought about a damper ring. They often use one when machining drums so they don't start "singing" and mess up the cut. But nothing I can think of would stay on reliably... nor would it fix the initial problem.
