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Bike starts like only half the engine is running

  #1  
Old 11-24-2014, 12:58 PM
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Default Bike starts like only half the engine is running

Couple weeks ago I accidentally hit the ignition switch immediately after turning on the power to my f4i, my bike started like it was only running on half cylinders until i revved it up a few times it started idling like normal.

After charging the battery at home i found it only had enough juice to start my bike once, any attempt there after would just barely turn over my engine leaving it momentarily in a weak idling state until revved up.

Figuring i fried my battery i bought and installed a new one. After, my bike started up and ran like normal until i shut her down and then reattempted. To my surprise i got the same rough idle like before as if i never changed the battery in the first place.

Not sure what to do from here, i could only guess maybe the alternator or some other link in the power system is fried after my early ignition attempt. Any suggestions, tips or advice on what to do is much appreciated. Thanks!
 
  #2  
Old 11-24-2014, 01:14 PM
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I don't think its a charging issue.

My first thought is your FPR.
 
  #3  
Old 11-24-2014, 01:59 PM
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^^ Interesting thought! This sounds like a real possibility now that ive read some about fuel pressure regulators.

If that was the culprit it would mean my bike is instantly losing fuel pressure once the engine is shut off and then struggling to regain normal pressure once fired back up again, only stabilizing after being revved up a few times.

So for now im reading up on FPR. Any others thoughts?
 
  #4  
Old 11-24-2014, 02:50 PM
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If the FPR diaphragm is leaking, it will put raw fuel into the intake. The bike won't like running on the extra fuel.

You could rule out the charging system with a voltmeter.

Do you have a Power Commander? They can fail and cause some issues too, although not as common as the FPR.

Other than that, connections have been known to come loose or burn. We need more info to go much deeper.
 
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