hey AGV...i am havin the same sort of trouble atm..
my lower cylinder is not workin aswell.
checked my sparks.they are ok.
checked/cleaned the carbs.they seem ok too.cloat needle etc closes everyhtin off nicely..
but i did find out that(if u read my topic "first run") taht the oil pump seal is out of place/damaged. maybe the same thing for you??dunno if this is related to my lower not firing good..but i think it maybe.i think i can see oil leaking from the lower exhaust port also so....
cheers
_________________
Philip Ahn
MC21 NSR250R
im poor...