Thank you Mike

The 250 Hyosung is a fairly common sight over here so I figure they can't be too bad.
It would seem the only thing stopping this from being a runner was a very badly installed carb - intake pipe O ring and the only thing stopping it running properly was the complete lack of any airbox innards. Both have now been rectified and runs and rides great!
Have noticed that on idle the headlight is very dim but brightens up with a few rpm and that the voltage across the battery only ever gets to about 12.6V. I would expect charge voltage to be up over 13.5V and that with a good battery the engine rpm shouldn't affect the brightness of the headlight too much so am thinking a regulator/rectifier issue?
A new one was only $25 from Hyosung Korea so have ordered it anyway... The month long wait is the painful part grr!!