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[Roadburn]

I Greatly Appreciate all the feedback I'm getting please don't stop. All the feedback is helping.  But I don't understand about all that compression stuff. This bike is a CVO FLHTCUSE2 with 110 cubic inch motor that has factory installed electronic compression releases. So I not sure how much compression this bike should have with them. But I do have both plugs installed with a spark tester that goes in between the spark plug and the spark plug wire that is sapose to light up when the plug fires. Still no spark. I have also tried just installing a third plug in one of the wires with a ground wire connected directly to negative in the battery. Also tried the other cylinder and another set of plug wires. I will be able to run a compression test tomorrow. I will run one test with the compression releases connected then unplug them and see what the difference is or is not.

[chicoman]

No compression, no spark, checking compression verifies that.

Sorry, but that isn't correct.  If you want to test for proper spark, you need to insert a test device between the plug wire and the plug, with the plug still installed.  Checking compression only tells you how much, if any, compression you have.  It tells you absolutely nothing about the secondary ignition system output.

Jerry

Your correct there, but he may have bent a valve by not letting lifters bleed down and cranked motor around to do the others, that would give low compression and maybe no spark. Testing compression would then give a better idea where to go next.

[Steve Cole]

I Greatly Appreciate all the feedback I'm getting please don't stop. All the feedback is helping.  But I don't understand about all that compression stuff. This bike is a CVO FLHTCUSE2 with 110 cubic inch motor that has factory installed electronic compression releases. So I not sure how much compression this bike should have with them. But I do have both plugs installed with a spark tester that goes in between the spark plug and the spark plug wire that is sapose to light up when the plug fires. Still no spark. I have also tried just installing a third plug in one of the wires with a ground wire connected directly to negative in the battery. Also tried the other cylinder and another set of plug wires. I will be able to run a compression test tomorrow. I will run one test with the compression releases connected then unplug them and see what the difference is or is not.

Just remove the small wire from the plug on the starter. Leave the ign. switch OFF and then jump the post where the small wire was removed to +12 with a starter button or something similar. This will turn the engine over and not allow the compression releases to work. If you want to check it with the compression releases then just plug the wire back in and use the original starter button.

[Roadburn]

Good news, there was no compression on the rear cylinder. I pulled the rocker box off and checked the push rods. They were back words so I switched them put it back together and had spark. Put the fuel tank on and it started. Thank all of you for all the info past my way. You guys were a great help. THANK YOU

[Twolanerider]

It's a rate of change circuit. If the starter motor turns the crankshaft at a steady speed then there is no compression thus no spark. If the crankshaft speeds up and slows down then we should be able to tell what cylinder is what by measuring when the speed up and slow down occurs. Now we know what's what, the ECM will begin to issue fuel and spark to the correct cylinders for start-up. Saves putting a cam trigger on the bike and the problems that go along with something else to fail.

Have had compression and spark on older bikes and have found the connection of lost compression causing no spark on newer bikes.  Never knew where the change occurred though.  Is it all Delphi, all 05 and later Delphi when the ECMs got smarter, all post-ACM Delphi?  I've no clue but am curious. 

[Twolanerider]

Good news, there was no compression on the rear cylinder. I pulled the rocker box off and checked the push rods. They were back words so I switched them put it back together and had spark. Put the fuel tank on and it started. Thank all of you for all the info past my way. You guys were a great help. THANK YOU

That's good news and congrats on getting it sorted.  That's great to read.  Even more so that it turned out to be something relatively simple that didn't have chasing a full tear down again.  Good deal .

[chicoman]

Good to hear, congrats.

[Twolanerider]

It's a rate of change circuit. If the starter motor turns the crankshaft at a steady speed then there is no compression thus no spark. If the crankshaft speeds up and slows down then we should be able to tell what cylinder is what by measuring when the speed up and slow down occurs. Now we know what's what, the ECM will begin to issue fuel and spark to the correct cylinders for start-up. Saves putting a cam trigger on the bike and the problems that go along with something else to fail.

Have had compression and spark on older bikes and have found the connection of lost compression causing no spark on newer bikes.  Never knew where the change occurred though.  Is it all Delphi, all 05 and later Delphi when the ECMs got smarter, all post-ACM Delphi?  I've no clue but am curious.

Reposting this question hoping Cole sees it and perchance knows the answer as I'm still curious.