Many thanks Steamcoaster & Discomania, I traced through the wiring and finally found a loose (or should I say broken) earth from one of the relays. So a quick 10p later and a little crimp and all is well with the world again. The wiring diagrams were usefull as it helped give me a starting...

When I say there is a knob i do mean the convoy switch (it has positions for various light settings), it works for the other light configs (side, no from lights etc). But would a problem with this cause the indicator to cease functioning too?

Just had a bad month, head gasket went just I was preparing to set off to get a new carb installed (almost failed last MOT). Engine is now running fine. But.... As i set off home from the mechanic I reallised that the indicators didn't seem to be working. Once home I check the indicator...

I've just moved to Hampshire, about 8 miles north of Basingstoke. My lightweight is due an MOT, since it hasn't really been in use a lot over the past 12 months I could do with finding a reliable local mechanic or garage that can just make things right and not cost the earth. Any suggestions...