I'm not familiar with the terrain between London and Brighton - will be going over, and therefore down, Ditchling? I think I've already mentioned that when I was 15 or so I used to ride a 1950s Philips roadster with a 3-speed SA and rod brakes, a long-term loan from a kindly, elderly neighbour. <moment of reminiscence for several good neighbours> Curiously I don't remember much up-hill struggling but I guess when you're a teenager you just do it, I do remember various downhills were you really relied on the awareness of others as there was no way of actually stopping. But I never crashed it, so it worked!