cam timing and igintion timing

Discussion in 'Engine, Fuel and Exhaust' started by ABRANGER123, Aug 10, 2013.

  1. ABRANGER123

    ABRANGER123 Member

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    I have a 1996 sportster with newer 1200 engine. Im installing a 1005 twin tec igintion and it says it need's to be on tdc on the front cylinder. The marks on the timing gear and cams align up when the rear cylinder is on tdc. Do the timing marks have to be align on the front cylinder in order to run correctly? I got the bike in the condition not running and someone try to put together. any help would be useful.
     
  2. tourbox

    tourbox Senior Member

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    Normally you time to the front cylinder. If you pull the Allen plug at the base of the cylinders,above the gear cover, you can see the TDC mark on the flywheels. There are usually 2 marks,a dot for advanced and a straight Vertical line for TDC. My manual only talks of the Dot for use with a timing light. Anyway once you have it at TDC for front cylinder look at your gears marks to make sure the line up. Sounds like it was gear timed wrong with the crank.
    You can also verify TDC by watching you Intake valve versus piston height.
    tourbox
     
  3. Slo-Ryd

    Slo-Ryd Junior Member Contributor

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    Tourbox has you covered. I use a long plastic straw in the front cylinder with the sparkplug removed and watch as it rises and stops. The vertical timing line on the flywheel should be easy to spot in the timing hole at this point. Center it and then verify all your timing marks on the cam side like he suggests and you will be good to go:s
    [​IMG]
     
  4. Jack Klarich

    Jack Klarich Expert Member

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    Good advice as always from you and Tourbox, you can also slide up the push rod tubes on the front cylinder , when the intake valve is closing look for the mark to be real close:s
     
  5. fin_676

    fin_676 Experienced Member Staff Member Moderator Contributor

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    If you are going to remove the gear case cover to check all the marks be aware that usually when you pull the cover off some of the cams will pull out with the cover
    You may require to remove the push rods to get the cams back in place
    If you have adjustable push rods then easy enough otherwise removal of the rocker boxes will be required
    As the pinion gear is keyed to the pinion shaft it is the start point for the timing marks and should always be correct due to the key
    Be aware that the gear case bolts are of different lengths i usually draw the cover on a piece of card and make a hole in each bolt position as the bolt comes out of the cover i place it in its relevant hole on the card

    Brian
     
  6. fighting213

    fighting213 New Member

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    I have a question on my 03 ultra when I took my cam s out to repair the worn out tensioners and found that the gears where off by one tooth I put it back to correct position now my question is did someone try to advance the timing or was this just a opps
     
  7. tourbox

    tourbox Senior Member

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    I would think it was an OOPS!!. Do you have it running again?
    tourbox
     
  8. fighting213

    fighting213 New Member

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    yes its running fine but the sound is a little different at idle maybe its me its one of those things that you hear, is it possible to advance timing like that?
     
  9. tourbox

    tourbox Senior Member

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    Yes, the mechanical timing. I've never done it , but would think it would run funny.
    tourbox