I just got a Brompton M6R and have begun using it to commute to work. It has been great except that I feel the position is too upright for me. I am now thinking of converting the M-Bar to an S-Bar. I won't be replacing the "M" stem which I understand is shorter than that on "S" series. This suits me just fine as I am used to riding road bikes.

My question is will the brake and shifter cables need replacing too?