I have a KZ 1100 that lost spark on number 2 and 3

Try to change coil from one side to the other, if the spark goes to 2 & 3 but not 1 & 4 you need the coil replaced or find the power loss (blown fuse) .I have not worked on that bike so am not sure. also color code on wires in the harness will be enough to follow wires without the book,no need to cut them open just note the colors at the point you are trying to check,follow along the way untill that color comes to a conector. or to the fuse buss or device.A multi meter can check condition between points Hope that will help you good luck .Joe

You bike has 2 coils. 1 fires cyls' 1&4 the other fires 2&3. Check the connections or you may have a bad coil.