Hard Start - BANG!

Discussion in 'Touring Models' started by Grillfish, Dec 10, 2011.

  1. Grillfish

    Grillfish Junior Member

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    This happened two times in the past two weeks. I go to start the bike after it's warm, wait for the engine light to go off, hit the starter and the engine turns over like 1 time and then BANG. Everything stops and I hear the fuel injectors/pump turn back on. When the injectors/pump turn back off, I then hit the start button again and it fires right back up.

    My OEM battery is 3 yrs old, could that cause it if there is not enough power? Could it be a start of a starter problem or maybe the compensator is going? Crank position sensor going bad?

    Thanks for the help. Just trying to avoid being stranded somewhere by myself.

    Ride safe and have fun.
     
  2. Hoople

    Hoople Account Removed

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    So as soon as you hear the "bang", you are releasing your finger off the start button and then re-applying it?

    The bang you hear is more of a single metallic knock sound, correct?
     
  3. glider

    glider Veteran Member

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    Like Hoople asked, is it a bang like a metallic or mechanical bang or is it like a fire cracker type bang out the intake or exhaust?

    A good and accurate explanation is needed to get a reply that may help you locate the problem.
     
  4. BUBBIE

    BUBBIE Well-Known Member

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    Hot starting my 09 FLHR after a stop like for fuel, It sometimes makes a Bang but starts,never does it Not start and like you Hear the pump cycle again...

    On mine, I think it to be the motor starting So Quick that it speeds up and Hits the compensator in the Other direction... I like the sound and it does wake up the other people in the area:naughty

    All look over in Shock and wonder What I Have :11:

    I will not get the SE compensator ,,,, IF and when mine needs replacing in the future,,,, I will go STOCK only...:s

    signed....BUBBIE
     
  5. oiler

    oiler Active Member

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    I was under the impression that this bang at start up is caused by a weak compensator. Just curious - why would you not replace it with the SE if it needed replacing??
     
  6. glider

    glider Veteran Member

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    The SE compensator has it's own problems associated with lubrication between the parts. Maybe someday Harley will perfect the part.

    The bang is the result on 07 and later bikes of a poor design right from the factory.


    signed....glider:D
     
  7. oiler

    oiler Active Member

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    Thanks for pointing that out. Was thinking of switching to the SE compensator because I sometimes get the bang at start up too. Guess I wil just leave it for now.
     
  8. Grillfish

    Grillfish Junior Member

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    Hi Hoople and Glider. Sorry for the delay in responding, was out riding before the rain comes.

    Yes, I'm releasing the start button as soon as I hear the bang, since the bang happens than everything stops, then the fuel starts puming up again. Once the pumps stop, I hit the button again and it fires.

    Yes, single metallic sound. Not an intake or exhaust bang.

    No issues today when I started it up 2 times.
     
  9. kemo

    kemo R.I.P

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    I have the same thing on my 2000 Electra Glide. It is a carbed engine.
    Ken
     
  10. Hoople

    Hoople Account Removed

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    I'm sure it is the compensator just bottoming out. I am running the SE comp and will also get that from time to time. After a long hot run, then turning the engine off for just a couple of minutes and then restarting it, I will get the bang and stall for a second. I no longer release my finger when I hear the bang and just "power through" the stall.

    During cranking, the ignition timing is retarded but I am sure it is not to zero degrees, so the risk of a kick back is always possible especially if low octane fuel is used. Don't think there is a whole lot you can do about it.
    The SE comp does reduce the frequency of the bang but as Glider said, they have their own problems with oiling.