Have you looked at previous threads on this brake? Most recently by gammakeith October 25 and November 15.
There is a wide range of opinion on the standard set-up – from, “the best drum brake I have used” – to, “it’s OK for the period” – to, “the brake that doesn’t work” – and, ” the confounded thing !!!” The latter comments tend to predominate.
My opinion – it can be made to work almost as well as it looks by doubling the leverage, in one way or another. A Vincent-style balance arm does it but requires extensive modifications and looks totally foreign. Retaining the original appearance, the best bet for now may be to halve the pivot offset at the handlebar ( gammakeith’s method, but he has twin cables and a compensator at the handlebar – Brummie system. Not quite so simple for a single cable, but do-able I think )
These solutions all double the handlebar lever movement and also double the forces in the system, so your thoughts about heavier cables are very relevant. It will inevitably feel more spongy, but you won’t mind that – given the much improved stopping.
