I assumed that one of the rubber bits on the cable linkage had gone, where the adjuster bit is. There was a clip holding the sheath on the ribbing so when you pressed the pedal there was resistance, but nothing on the other side holding the sheath so the sheath and cable would slide back through the rubber mounting thing together, hence no pedal travel.
I fitted a new cable today but the problem remains. What am I missing and how can I get hold of it quickly! I can't work it out from the parts diagrams which bit has fallen off.
