Sorry, I should have explained further, there is a healthy reading from the battery, rectifyer, coils & the live feed to the capacitor. However, there is a poor reading from the capacitor itself & zero reading from the negative wire to the capacitor.
When you press the horn on my bike, it works wether or not the ignition is on or off. Now the horn doesn't work or the lights, brake lights etc. There is zero reading at the horn. The bike doesn't even cough when you kick it over (its always a first time starter). The red (live wire to the capacitor had broken off at the little connecting spade. I re-soldered it but to no avail.
Thanks for your replies.