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Lack of Power

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.
 
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Hoople, thanks for your comment.
What is puzzling me is the carbon built up in the front cylinder which only happens when on road but not at idle. This seems to me to indicate that there is plenty of fuel but little combustion at higher speeds.

Is it time for prayer????

Willie
 
Praying probably won't help.

When dealing with a problem like this you must collect supporting evidence. You will go nuts trying to out guess the circumstances.

If you strap the fuel gauge to the bike and read the pressure under actual demand, that eliminates 10 possible parts & "what if" reasons. Put together a quick and dirty coil tester and eliminate another 10 possible parts and "what if" reasons.

You need absolute concrete answers to some questions or you will find yourself coming back to the beginning and double checking yourself.
 
Hoople, thanks for your comment.
What is puzzling me is the carbon built up in the front cylinder which only happens when on road but not at idle. This seems to me to indicate that there is plenty of fuel but little combustion at higher speeds.

Is it time for prayer????

Willie

I think you have a very good understanding of the troubleshooting process. It is all about the process of methodical, step by step elimination. From your comments I believe you will eventually uncover the culprit here. Just wish it was today. Keep grinding and let us know what the outcome is. I note that the young staff at most dealerships does not possess really good troubleshooting skills, so they normally just start throwing new parts at the problem till they get lucky. Expensive.
 
Bubbie, Took off the cam cover and everything appears normal (see attachment) 1st time to attach so here goes

View attachment 6507

I did like the way you said it only means taking off the cam cover, & crank bolt......plus the exhaust LOL.

It's time to move on to the coils but I was also convinced it was the cams so at least I can dismiss that now. Thanks Bubbie for filling my morning.

Willie

willie,

I gave it a lot of thought before i hit the send button..... Hahaha

I remembered a mechanic telling me once long ago he thought he torqued it to specks(cam gear)... Musta been coffee time and it was tight but Not Torqued. Glad I went back in to check.
Nice photo tho and IF I were There with you I would of Turned the wrenches! If you allowed.

Still like the coil Idea.
Are you sure this isn't a test given us, that the "big guy" set up to see who and what and Why???

Put your finger into the dyke.... No, over into this leak, No it is leaking over here Bigger.
We're running out of dyke and Fingers, so I hope the problem gets solved soon...

HuMmmmm a Test?

signed....BUBBIE
 
I have been following this with great interest like a story. A suggestion from an aircraft mechanic if I may. I have noticed were everyone is giving suggestions that are plausible, but have you looked at 2 places yet (sorry if I missed them) the fuel line from the tank and the tank itself. I say this because I had a turbine engine on a Huey that would run fine until you put it under a load and then it would start acting like you took the power away from it. We spent many a day and night tearing that engine down and doing all kind of diagnostics. Finally an old mechanic suggested we check the fuel lines, sure enough the primary line from the fire wall to the engine fuel control was partially obstructed from the inner wall developing a blister. Later in years I ahve seen trash obstruct partially a fuel line, I have seen fuel filters put in upside down that would do the same thing. So the point is you might want to check to see if the fuel if unobstructed from the tank all the way to the engine.
 
The sooty jug is the wrench in the spokes. I't could be the clue to help eliminate lots of "that ain't it", or it could be causing one to chase his tail. One of the first laws of logic is "correlation does not necessitate causation."

You could have multiple failures. it is less likely than the single cause, but it is possible. I would do the easy first: swap the plug wires (if possible), then if no dice, swap the coils (again if possible). If still no joy, I'm inclining toward Hoople's fuel supply. It's that stinking sooty jug bothering me there, but still, if I did not know about the sooty jug, I'd be jumping on inadequate fuel at higher rpms.

Just thinking out loud again. However, systematic and methodical elimination of possibilities is the best approach. Go from most likely and work your way to least, include the characteristic of ease of performace as well.

I'm sure of this: When the cause is found, we will all have learned something, and respond with a "Doh! Of course!"

Carry one. Patience will win out.

Enjoy,
Rich P
 
Will swop coils and leads tomorrow and if problem shifts to rear cylinder then I know it is coils, right?
Went to HD dealer today and asked if he checked fuel pressure at load and he said he reved it....eh?
Can I borrow your pressure gauge to do a road test. "Oh no it's too dangerous, the equipment is delicate, if a leak occurred on the road, with hot exhaust, oh no!!!"
After the coil test, will look at the tank and fuel filter. I assume if pressure is good from the pump at idle it should be good, full stop! bar restrictions in fuel filter/line.
I can imagine from the places I have been in the last year, Yukon, Alaska where there is a gas pump at the side of the road, just plug in the credit card etc, no kiosk, no humans!!! That there is a real possibility that there could be a lot of sh*t in the tank that I actually paid for but didn't want and could now be announcing its existance by blocking up the filter to some degree,
These are the only two options I now consider feasible but am open to any other suggestions.
Oh, just for a laugh, I did recount my woes to the dealer and his response was as follows "So it won't go more than 60mph, have you considered trading it in, sure most of the guys around here don't go over 60mph anyway"

I am losing my faith in the human race!!!

Willie (EDIT off but enjoying getting to know the ultra more intimately)

For those reading my last post, the word "EDIT" can be interpreted as meaning " Not in the best of form at this particular time"
I thank Hobbit for substituting a shorter version of my original word.
 
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The way the bike is right now is in it's factory stock configuration, that is no fueler boxes, no add on black boxes, pure stock ignition system,,ignition is triggered from the ECM,, factory map and look up tables. ?.
 
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