i have a 1990 kawasaki ninja 600c zx6 running bad?

Question

its running on cylinders 1 and 3 not 2 and 4 checked fuel, ok compression,ok has spark

Answer 1

The fuel may be OK.
The cylinders might be getting fuel. But not the correct amount at the correct time.
The # 1 problem in this situation is dirty carbs. Remove and clean them.

Answer 2

Dont overlook the possibility of fouled plugs, An electrical problem is unlikely because the 1 an4 cylinders fire at the same time as do the 2 and 3 cylinders, in whats known as a wasted spark ignition system, they call it that because as 1 and 4 do fire together only one or the other is on the compression stroke the other is on the exhaust stroke and the spark is "wasted"same for 2 and 3, If the problem cylinders were either 1 and 4 or 2 and 3, you could have an ignition problem, Check that the wires from the coils are going to the right cylinders, as your sitting on the bike the cylinders are numbered from left to right 1234. make sure the wires that go to one and four are from the same coil, and that 2 and 3 are from the same coil. Dirty carbs however are the most likely culprit, clean them and CHECK FLOAT LEVELS! also when you reinstall them, install new plugs and sycronize the carbs, (or have this done in a bike shop) Please do not try to syc. carbs by ear, THIS NEVER WORKS!. Valve clerance is unlikely on 2 cylinders at the same time, but if they have never been checked, you should get this done, probabably a good idea to have this done at a reputable shop by a qualified mechanic. I hope that helps and good luck

Answer 3

What about the Valves timing. I don't think you have convered all bets yet. Have you tried new plugs. Just getting spark outside of the Engine does not prove that the spark is sufficient to ignite the mixture.

Answer 4

Check your valve clearances.

Answer 5

try clean carboraters my brothers did the same thing make sure they are intune to each other