Hoople
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I doubt the coil is running out of steam. If it was, the spark would fail to jump the gap which would result in an engine miss, and not what seems to be the engine nosing over and running out of power. How I understand it, the bike is not "jerking" when it tops out.
It is more like a lack of fuel VOLUME. We may test good pressure at idle but that says nothing for the amount of volume the pump can deliver when high demands are needed. For instance, (not saying this is the problem) a restricted fuel filter would have little effect on fuel pressure during low demands of volume but would have a tremendous effect on pressure during high volume.
But if you think it's the coils, test them with a home made high demand gap.
The fuel pressure adapter that HD uses to check fuel pressure allows you to run the bike while testing fuel pressure. What needs to be done is tape the gauge to the bike and see what the pressure is during a street run. The pressure must remain at 55 PSI from idle to top RPM UNDER LOAD. Just goose-ing the rpm while bike is in neutral does not tell you much.
You have to confirm fuel pressure under dynamic conditions so that can be eliminated from the equation.
It is more like a lack of fuel VOLUME. We may test good pressure at idle but that says nothing for the amount of volume the pump can deliver when high demands are needed. For instance, (not saying this is the problem) a restricted fuel filter would have little effect on fuel pressure during low demands of volume but would have a tremendous effect on pressure during high volume.
But if you think it's the coils, test them with a home made high demand gap.
The fuel pressure adapter that HD uses to check fuel pressure allows you to run the bike while testing fuel pressure. What needs to be done is tape the gauge to the bike and see what the pressure is during a street run. The pressure must remain at 55 PSI from idle to top RPM UNDER LOAD. Just goose-ing the rpm while bike is in neutral does not tell you much.
You have to confirm fuel pressure under dynamic conditions so that can be eliminated from the equation.
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