Motorcycle Repair: no spark in cylinders 1 and 4, 1980 honda cb750f, yellow wires

Question
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Followup  Hello Mr. Shively.  Thank you for your response.  I am new to working on my bike and have no tech schooling but will try to explain to you.  Using the Clymer manual I worked in reverse starting at the sparkplugs.  Since I knew the #2 and #3 cylinders worked I swapped out the plugs and plug wires first.  They didn't work in the #1 and #4 cylinders, but the #1 and #4 swapped plugs and wires worked telling me that they were okay.  Same thing with the ignition coils.  Right side swapped for left worked but no spark for #1,#4 cylinders.  This told me the coils were okay.  Same thing with the spark units.  Both units sparked on the #2,#3 cylinders but not in the #1,#4.  This told me that they were alright.  The pulse generator would generate a pulse  to both spark units telling me that it was working.  The only meter work that I knew how to do was to test the resistance on the pick-up coil assembly as per the manual.  The only problem that occured was with the testing of the blue wires.  The yellow wires tested at 530 ohms as per the manual.  The blue wires tested at 530 ohms at first.  When retested it didn't register at all.  On the following tests it read 530 ohms again.  I thought there might be corrosion on the connection giving a bad reading so I cleaned and retested and got the proper reading but still no spark.  Am I doing something wrong?  Again.  Thank you for your help.   Anthony
Question -
Hello.  I have a problem with my 1980 Honda CB750F motorcycle.  There is no spark in the #1 and #4 cylinders.  I replaced ignition coil with a known good one and still no spark.  All spark plugs are good.  Sparkplug wires good.  Coils good.  Pulse generator good.  I thought that the spark unit was faulty but changed it with known good one, still no spark.  I could find no breaks in the wiring either.  Any ideas?  Did I miss something?  Any help is appreciated.  Thank you for your time in this matter.     Anthony
Answer -
Hi Anthony,

Describe exactly how the ignition components were tested. What were the meter readings, if any?

I return test and repair information files by email. Be sure to include an email address.

We'll go from there...

Respectfully,
Mark Shively  

Answer
Anthony,

Very good description, Thanks!

Your testing method is common sense and a very good approach that professional tech use. Meter readings will vary for a variety of reasons. I suspect the pick-up coil and the blue wire are working normally.

Send me an email so I can return tech files.

This correspondance will grow rather long if I cut and paste these tech files here.

mshively1@woh.rr.com

Mark Shively