coil pick-up question

[XSessiveForce79]

so...on my 79XS I have no spark..and in my checking things out I come to the 4 pin connector at the TCI and find 730 ohms between red/white & green/white. but cannot get a reading or value between yellow/green & yellow/red.Should I still get spark to two of my cylinders ? on my parts bike I took the pick-ups out and at the connector right on the end of the p/u assembly I get 720 ohms between black & orange..and cannot find any readings from any other combinations of black to blue...or gray..or any other combinations..is this p/u assembly good? Lots more questions,carbs ,exhaust,performance. anyone from around Hopkins , MN ?

[3Phase]

<eecummings>
Welcome to XS11 If you took the pickup assembly out of the engine you should be able to see which wires go to which coil If you have continuity for one pickup coil but not the other that pickup coil is bad so you should replace the bad pickup coil but make sure you are checking the resistance at the coil otherwise it could just be a bad wire between the TCI and the coil and you would replace the coil assembly for nothing and there would be no spark because the ignition still would not work
</eecummings>

[79XS11F]

TCIs can be bad but my own experience is that is in not all that common a problem. I would start with checking the coil to plug wires. They tend to corrode and the corrosion works its way up the plug wires. Check them. If they are all hard as rocks they are likely fully corroded inside. If they seem OK, cut about 1/4 of an inch off the plug end of each one and thread the plug boots back on. This will give you better positive contact between the plug wires and plug boots.
Check the connections between the coils and the wiring harness. Make sure they are clean and tight.
Next up is the pick up coil wires. Make sure they are not broken inside the wire insulation right at the folds under the timing wheel. This is a known issue with the XS1100s.
Rob

[Lamric]

...on my 79XS I have no spark... and find 730 ohms between red/white & green/white. but cannot get a reading or value between yellow/green & yellow/red.Should I still get spark to two of my cylinders ?

Normal advice is that a broken pickup wire will only take out two plugs but I have had it take out all 4 plugs. My '80 SG had no spark across all four plugs, took a lot of head scratching and parts swapping before I realised it was 'just' one pickup wire that had broken.

Fix the pickup wire.