Ok....had the bike on for about half an hour one day and randomly switches off, try to start again and the it tries turning over but cant (sounded like battery was dead). So roll started it and it was running.......now everytime i come to turn it on i have to roll start it cause it doesnt work with the electrical start, acts like the batteries dead. Anyone got any idea what this issue is?

Sounds like the electrics. The charging system may be kaput (very common problem) and could have knackered the battery.
Go through the checks on this document:

http://www.400greybike.com/docs.htm

and also read through the Haynes manual in the REF section.