Shovelhead ignition gremlin...heres a good one for ya!

[Warhorse]

Hello...new to the forum...this is my first post.
I have a 1977 FLH (basically converted to an FXE). Wiring on the bike has been stripped and simplified.
First a list of the new parts on the bike to eliminate them right off the bat. Most have also been tested and work fine.
ignition coil, battery, battery cables, solenoid, points, condenser, plug wires, plugs, starter button, voltage regulator

Here is my problem: In trying to time the bike we were not getting the timing light to "strobe" when hooked to the front cylinder. We hooked it to the rear plug wire and it strobed fine. We figured the front plug was bad as it was old. Replaced front plug (so both were new...NGK BPR5ES), hooked timing light to it, still no strobe. Checked spark at front wire...good spark. Flipped the plug wires on the coil. Now the front wire strobed, but the rear did not. Swapped coils with one we knew was good. Same thing...one wire strobed the light, the other did not, both emitt enough voltage for a good blue spark, yet the bike still only runs on one cylinder. Tested wires for resistance and all looked good.

Any ideas?????? My buddy is a bit of an electrical guru and this one has him stumped.

[Nightking]

Originally Posted by Warhorse

Hello...new to the forum...this is my first post.
I have a 1977 FLH (basically converted to an FXE). Wiring on the bike has been stripped and simplified.
First a list of the new parts on the bike to eliminate them right off the bat. Most have also been tested and work fine.
ignition coil, battery, battery cables, solenoid, points, condenser, plug wires, plugs, starter button, voltage regulator

Here is my problem: In trying to time the bike we were not getting the timing light to "strobe" when hooked to the front cylinder. We hooked it to the rear plug wire and it strobed fine. We figured the front plug was bad as it was old. Replaced front plug (so both were new...NGK BPR5ES), hooked timing light to it, still no strobe. Checked spark at front wire...good spark. Flipped the plug wires on the coil. Now the front wire strobed, but the rear did not. Swapped coils with one we knew was good. Same thing...one wire strobed the light, the other did not, both emitt enough voltage for a good blue spark, yet the bike still only runs on one cylinder. Tested wires for resistance and all looked good.

Any ideas?????? My buddy is a bit of an electrical guru and this one has him stumped.

Ok, just so I have this right. Were you trying to time the bike running on one cylinder?

[claydbal]

do you want the quiz to remain strictly electrical, or do you wanna give more details to correct the problem.

hint, that ignition fires both plugs at the same time. one side could be weak enough not to fire under compression. static time the plate, double check points, and replace condensor. if you used 55 chevy 6 banger points, did you drill the hole ?

[Warhorse]

To Night King...no, we werent trying to time it on one hole...when we went to time it we discovered it was only running on one.

To claydbal: we static timed it first and have rechecked and reset the points several times to be sure...points are new Blue Streak, as is condenser.
Understand that spark outside the combustion chamber isnt the same as spark under compression, but its done it with 2 different coils now, one off my wifes Sportster that I know to be a good coil.

[nmaineron]

There is something going on with the original front plug wire.It doesn't really matter if you are using resistant wires or not,but the sensor on the timing light is not picking up on that wire.If you are static timing it right there is no need for the light anyway.

[Warhorse]

Dont think it's the front wire...it does it with both wires...it just depends on whichever wire is plugged into the top plug wire terminal on the coil. Whats weird about it is that it's got good spark out of both wires, but maybe its not good enough. Not the coil though, cuz it does the exact same thing with the coil off my wifes Sporty, a coil I know to be good.
My buddy and I are leaning toward the condenser. I think we are gonna mess with that tomorrow.