Tuning issues?

Discussion in 'Engine, Fuel and Exhaust' started by Benmedley, Jan 12, 2011.

  1. Benmedley

    Benmedley Member

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    I have a 2004 Road King and 3000 miles ago,put S&S 510 G gear drive cams,in it,true dual exhaust,K&N air cleaner,Screamin' Eagle performance ignition module and it absolutely will not rev up and has sluggish performance.Also,I tried to top it out and at around 95mph,it seemed like it ran out of fuel-it choked out and nearly died.I feathered the throttle and it came back to life -some.It won't accelerate and my fuel mileage is awful-around 30 mpg.The carb is a cv that has an adjustable needle and the jets were changed to a 52 pilot and 205 main.45 and 190 are stock for this bike according to the manual.I have heard everything from timimn to sumping may be the problem.There is no oil spewing out the head breathers,and I took the cam cover off 2 times and the timing marks are dead-on.I am at a loss and want my bike to run as good as it can.I am planning on a dyno-tune when the weather gets better.Thanks for any advice ahead of time,Ben.
     
  2. Hoople

    Hoople Account Removed

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    Almost sounds like the spark advance is fixed & not moving. I am not familiar w/ the SE performance ignition. How is the basic timing set and what defines the advance curve. Would you have a link to the instructions that comes with the unit. I would like to take a look at them.
     
  3. Benmedley

    Benmedley Member

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    It is a non-adjustable unit with (I think) a 5 degree difference in either advance or retard-i will check-from stock and a 6200 rpm rev limiter.
     
  4. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

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    Those are pretty big jumps in the jets. Do you have any other jets between these two extremes? I would try incrementally increasing from the stock jets up.

    When you say you have an adjustable needle, what are you talking about, the idle air/mixture screw or the main needle? And by adjustable, do you mean with the circlip in the slots at the top of the needle?

    See here:

    *Twin Cam CV Carb Rejet Suggestions - Harley Davidson Community

    TQ
     
  5. ultra...good

    ultra...good Banned

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    Have to agree, the only time you go up that far with jet sizes is if you go up real big with the bore. You will need somewhat bigger than the stock jets, but you went way too far. Go smaller with the jets, and let us know what happens.
     
  6. Bodeen

    Bodeen Well-Known Member Staff Member Moderator Contributor

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    I agree with all that has been said already. A .46 would probably be enough with an adjustment to the mixture screw. The 190 may also be enough with a couple washers under the needle. Let us know how it works out.

    Bodeen
     
  7. Benmedley

    Benmedley Member

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    it has both an adjustable mixture screw and a needle with circlips.Will a too rich carb cause the symptoms i have described?
     
  8. Bodeen

    Bodeen Well-Known Member Staff Member Moderator Contributor

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    Is it backfiring? If so from where? How does it idle?

    You need to start with making the bike idle porperly and then move to speed part.
    Check out the link given to you by TQ.

    The fact that your fuel mileage is poor (riding style has a lot to do with this).

    "I feathered the throttle and it came back to life -some."

    Not sure what feathered means but if it means it got better when you let off the throttle, indicates a rich condition. At 95mph (see riding style above) this would indicate the adjustable needle is set much too high.
    If the only mods on the bike are as you described, its way overjetted. IMO

    Bodeen
     
  9. BUBBIE

    BUBBIE Well-Known Member

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    MY BET would be the jets ARE too big. Go back to 45/190 as the biggest.
    I DON"T think the jets are causing Your Problem. It is more likely,,,,,,,

    The Carb is Probably NOT set correctly in the Float position, causing a LEAN condition and LACK of fuel when needed..

    If the exhaust is Black, and Check the plugs to see what they look like.....(report back)

    It probably IS Too RICH until you demand the fuel THEN it Might be Too Lean because of the float setting too low....

    The screw adustment i think IS the Idle adjustment...1.5 to 2.5 max. turns out.. Seeing slow speed jet is larger than stock recommended, it may be too Rich there to start with.

    I would CHANGE the jets Back to Stock like Bodeen mentioned and TAKE out the SE Module just to try without, Using the stock one.

    I want to know HOW the lifters are adjusted (stock pushrods) ????? OR

    Are they done with fully adjustable and CORRECTLY set??

    This above could be a factor Also..

    Give me a Reply to my questions-suggestions and Ill go from there.

    signed....BUBBIE
     
  10. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

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    Yes. If you also have a strong smell of gas, and your plugs look real black and gummy/tarry, I would be pretty sure that the jets are flooding. Those cams by themselves with the Stage 1 will not need that much gas.

    TQ