hey guys i have a problem with my 1989 cbr f1 its miss firing cyl 1 and 4 are firing 2 and 3 are not i have fuel and good spark i thought it may have been the coil at first so i replace both of them now on all 4 wires i have a healthy blue spark but 2 and 3 still wont fires my question is whats next to check? i compression tested the bike when i first got it and it has 150psi per cilander the bike runs on 1 and 4 but doesnt sound like a normal missfire it bogs dosent studer or run rough . but i know its not fireing on 2 and 3 because i pulled the wires off the 2 and nothing changed it didnt run worse any ideas please help because im out of ideas thanks for your time by the way i replaced the plugs to

 

Are the spark plug wires routed to the correct cylinders?

 

I just had this problem recently, ill almost out money on the fact that your plug wires are mixed up..... If sitting on your bike left coil fires cylinders 1and4 right coil is 2and3...... Sitting on bike number 1 cylinder being far left and 4 being far right in order..... Hope this helps

 

Bet money*