[1986 Yamaha 600FZ]

Yes Cynic you are right cleaning all the connection and ground points 

[1986 Yamaha 600FZ]

1 and 4 no spark 2 and 3 dose have spark.  but if I put the plug that goes from 2 and 3 coil pack to 1 and 4 coil pack they spark

[1986 Yamaha 600FZ]

1 hour ago, Cynic said:

Swap the coils over from left to right.

If the problem swaps its the coil. If it doesent you have proved all the plug leads and coils are good.

 

I did the swap and the other two  works and the other two now is dead so both coil works. the yellow plug that goes to the first coil is dead and the white plug that goes to the other two works fine could it be the CDI going bad?

[1986 Yamaha 600FZ]

Hi there dose anyone know why on my 1986 Yamaha Fz 600 why  am I only getting spark on two plug and the the other two I am not getting spark I try new spark plug check all fitting all looks good.