I'll definitely check the Exup cables etc... tonight Paul, cheers... That's a good point. I've serviced the Exup dozens of times; however it's easy to get complacent!
The air filters a very good point too Mike. I've not actually checked it since you Ivanised it 3 or 4 years ago! How bad am I...!!!
Cheers guys... I have planned to spend this evening diagnosing my issue. Now after your comments I'm looking forward to getting home and getting dirty lol... I'll let you know how I get on...