Honda SH125i 55 plate

hey all

need a little help, my brothers SH125i is playing up a bit, it wont sit idling properly at the lights, also when slowing/breaking to turn into say a side road it sometimes cuts out if the revs drop too much.

i have replaced the spark plug, that snot worked, im trying to find the idling adjustment screw, but i cant find it!! nor can i find any online manuals.

im thinking its either dling speed, fuel filter maybe, or somethign to do with the FI?

wotch rekon gang? any ideas, oh and anyone knwo where the ferking idle adjustment screw is??

lambda sensor is caput