I just came back from a quick ride on my 1968 r60/US with 33,000 miles . When applying the rear brake, I would get a metallic squeal from the rear whel. ..only used the front for the ride hoe! Luckily it was a short country road ride. Before I take off the Old European bags to remove the wheel, how can I adjust the brake .I assume it is via the threaded rod on the right side of the wheel.