As suggested, check the earths.

Thanks a lot for all your help guys, given me a few more things to think about, I'm going to try everything suggested on monday, is there any chance it could be the pulse generator? I wondered if that was sending the wrong signals to the CDI (or none at all)?
Thanks again.

Check the easy stuff first.

Random gauge action is earth related ususally.

Check the one by the coil on the left hand side...mine was loose and I got misfires, temp gauge sweepeing like a tacho and lots of random activity!

Ok, today i've been through the earths (again), all fine. The connections for the coils were dirty so i've cleaned them, checked the fuel tap and vacuum, all fine. played with and cleaned connectors from the pulse generator and alternator, checked battery voltage on and off charge both very healthy.
unfortunatly at the moment i'm out of funds to throw at it, so it returns to its home where it will stay untill some kind person suggest something or I boot it towards a garage.

I'm quite handy with most things but I've never known carbs and NC30 ones look fairly complicated (correct me if i'm wrong), and theres four in a fairly tight space.
I was fairly sure it was electrical but the only thing left is the pulse generator, if it is fueling i don't think it will be me fixing it.

Thanks for all your help, sorry theres no result yet. Any other suggestions will be more than welcomed.

Check the earth at the back of your tacho. Its attached to the clocks frame.I've had a similar problem & found this earth loose. tightened & sorted.

Thanks Emto, I didn't know there was an earth there? I had a look today couldn't find one, could tell me where abouts it is? thanks.

Ok, today i've cleaned up that earth, and still no good. so this afternoon i've pulled the carbs off, i'm gonna clean them tonight. wish me luck.

It's straight forward to do them, just whip the bottoms off and work on dismantling and putting them back together 1 at a time.

Don't unhook the linkages just remove the jets, float etc and clean them all up.

Ok, happy days (i think).
Had the carbs off, checked all the diaphrams and cleaned everything, didnt seperate them. When i got to the float chamber of the rear left carb, i was amazed it was even running, covered in a rusty coloured residue completely blocking the main jet! (pictures soon)

So its all nice and clean now and back on the bike, but silly me reset the mixture screws to 2 turns out and now it just doesnt seem to idle right, possibly too rich and quite lumpy.

when i first fired it with the carbs back on it idled around 3000, so i turned it down to 1300 and it just seems like its going to stall?

I have access to an emissions machine and was thinking i could use that to set up the mixture properly, but i have no idea what data i'm looking for.

Whats the best way to find if your bikes rich or lean?

(and thanks to everyone for thier help, i really was sure it was electrical. nevermind.)

If your carbs are fitted correctly and the bowls, jets etc. are clean then a lumpy idle is down to the carbs needing balancing.

Tony