OK...
Drained the bike last night. - couldn't see any water in the petrol...
Refitted the plugs after letting then dry again and tried again. Still nothing.
Took the plugs back out again to check that they were both wet - and found the back one to be perfectly dry, the front still wet so I am assuming that I have ignition issues on the front cylinder. Looking into the carbs when turning the engine over it looks like there is petrol going into both cylinders - you can see the droplets in the venturi of the carbs.
Does anyone know How I can tell if I am getting a spark to a cylinder without sparking the plug against the engine and blowing up the ignition module? (Things are soo much simpler with points ignition

)
Other than that does anyone know what is the most likely component to break on an SV that would cause no sprak to the front cylinder?
Thanks in advance
Stu