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No spark after coil change

dofilus

CB750 Member
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Hi guys, i really need some help now!! I´ve just bought a -77 cb750four, when i got the bike it worked like a Clock. I discovered that the original ignitionwires were totally lost!! The Cables were so old and dry so they broke down when i moved them to check the sparkplugs, I´ve bought a set of new coils in the uk at ebay for sohc Engine and mounted them on the bike today. They don´t seem to work!!
No spark at all at the plugs!! Í took the black/White Cable from the bike and connected to + at the coils, blue and yellow from the pointbreakers to each coil, blue for 1-4 and yellow 2-3. I also mounted an extra ground from the frame to the mounting screws but there are no sparks....
Have i missed something or done something wrong?????
 
Are the new coils the same design as the original ones or removable plug wire type? First verify you swtill have battery power to the coils. Then I would start checking resistance values of the coils themselves. If the only thing you changed are the coils and nothing else then it has to be bad coils unless you didn't hook something up properly.
 
They are "oem" style. They fit but not like the original one, i check the resistance tonight and i have resistance at first but after 10 turns on the Engine the resistance is gone. I´m waiting for answer from the store in uk but i Think the coils are crap.
 
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