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. 

I have no idea.. but it is good to head over to the new members section before asking a question as lots of people ask a question and then disappear. Also would be good to see pictures (of the bike, not sparkplugs)  and welcome to YOC - Sure someone will have some suggestions to help

Coil pack knackered

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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.

 

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?

So which two aren't working after the coil swap?

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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

Which plugs are you swapping exactly?

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You need to be clearer on what you are swapping. Youve lost me

You need a meter,  switched to Ohms,  see what the pulser coils [ on stator,] are putting out, also ,disconnect ALL connections to CDI, AND CLEAN ,,  corrosion will be the cheapest fix , CDI" rarely go wrong,

Woah people.

Form an orderly que. Unless I'm really off the ball he has swapped the coil connections between coils. So the fault has swapped from 1 and 4, to 2 and 3.

From that I say the coils, plugs and leads are all good, now we move on to the pick up coil(s?) and the cdi and its connections. I don't kow the fz in any detail so i'll shut up now.

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

Don't know if you got it sorted but when that happened to my fz600 it turned out to be knackered pick up coils.