I've only had my '51 Champion a few months and the brakes worked fine when it arrived--not strong, but fine as far as stopping straight without lockup. A few weeks ago I was driving it after a rain and as I was coming to a stop a rear brake locked up. I wrote it off to wet roads and everything seemed fine after that. But the next couple of times I took the car out a rear brake has continued to lock up easily, even when I try to stop slowly and carefully with light pedal pressure. What's happening? Does the car just need a brake adjust? It has the hill-holder feature and I'm kind of suspicious of that, mainly because I don't really know how it functions as part of the braking system. Does anyone have any suggestions as far as where to begin looking for the problem?Thanks.