bike not happy

Hi
Ive just purchased a ZZR 600 1996 model
When i got it the bike wasn't running smooth and wouldn't idle.
Ive pulled the carby's apart and fully cleaned them and also replaced the plugs but it still runs rough, all the cylinders are firing but it sounds like the timing is out?? is this possible?
Ive also checked the fuel pump and everything works fine when i ride it the bike starts off sluggish but once the revs come up its not too bad but still not perfect.
It really feels like some kind of spark issue or ecu problem any suggestions would be good
Cheers
Ive just purchased a ZZR 600 1996 model
When i got it the bike wasn't running smooth and wouldn't idle.
Ive pulled the carby's apart and fully cleaned them and also replaced the plugs but it still runs rough, all the cylinders are firing but it sounds like the timing is out?? is this possible?
Ive also checked the fuel pump and everything works fine when i ride it the bike starts off sluggish but once the revs come up its not too bad but still not perfect.
It really feels like some kind of spark issue or ecu problem any suggestions would be good
Cheers