93 gsxr 1100w rough idle and poor running-why?

[johno74]

Hi everyone, im looking for some help with my gixxer pse.
its standard as far as i know apart from micron and k&n filter gauze in standard airbox.
problem is that idle is really rough/lumpy and its difficult to start

what i do know is that plug 1 is sooty black whereas 2,3, 4 are tan/brown. i havent changed settings on carb but obviously somethings not right.
i have renewed plugs caps coils and fuel. checked tap and petrol pipes. psi on each cylinder 155. 
anyone sorted a similar issue?
thanks in advance

[kokolis]

Carburator synchronisation would help.

But valve clearance, clean air filter and plugs (all ready done) first must be sorted