Thanks for these replies, guys. Sorry for the delay. Been spanking the bike on the Isle Of Man. See pic of my bike admiring the view during a piss break.
I am in Hull.
My bike uses double the amount of fuel a 2012 ktm 200 uses and 1.5 times the amount of a 2004 ktm 200.
It splutters in the low revs, at tickover it usually stalls but sometimes revs high. It starts very well but needs a handful of throttle.
I put a 250/300 gnarly on, in the hope it would help without needing jetting but the problems are still there and now I just seem to have lost top end with no bottom end worth having for the sacrifice.
I don't really know whether to start the jetting with the standard pipe or the gnarly, I thought I read somewhere that gnarly pipes don't need jetting. I can't really believe this but if true I could start with the gnarly on.
I am up for taking the carbs off and having a go. But after that, if it does not improve significantly, I would gladly take it to this guy in Durham. I work up there once a week anyway and have a trailer.