1980 - 84 BT timing specs?

Discussion in 'Engine, Fuel and Exhaust' started by dynarider, Jan 9, 2014.

  1. dynarider

    dynarider Member

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    I've got these timing numbers from the Clymer '59 - '85 Sportster manual (points until 1979)

    ign. retarded 1959 - 1971 15 (degrees BTDC)

    ign. advanced 1959 - 1971 45 (degrees BTDC)

    ign. retarded 1972 - 1978 10 (degrees BTDC)

    ign. advanced 1972 - 1978 40 (degrees BTDC)

    1980 - 1982 (degrees BTDC)
    Start 8
    Fast idle 20
    2,000 RPM + 40


    Does anyone have similar information for the 1980 - 1984 BT's, FLH, FLT, FXE, FXR?

    Thanks! I'm looking at using a newer ignition on a '72.


    -- Sent with :)
     
  2. Jack Klarich

    Jack Klarich Expert Member

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  3. Jack Klarich

    Jack Klarich Expert Member

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    Stock ignition rule of thumb start @ 35 degrees
     
  4. dynarider

    dynarider Member

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    I have points and am thinking of going electronic to lose the points and mechanical advance unit. These older ignitions are a little scarce. Some of the newer models go as far as 55 degrees advance & 40 degrees is what I'm shooting for.
     
  5. Jack Klarich

    Jack Klarich Expert Member

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    Keep in mind the width of the timing hole accounts for about 10 degrees:s
     
  6. dynarider

    dynarider Member

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    I suppose you could compensate for a unit with 55 deg. advance up top, but that would leave like zero or retarded at idle. Kind of like a pipe for low end or top end, and you can't get both from the same pipe.
     
  7. Jack Klarich

    Jack Klarich Expert Member

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    Too much is too much and will cause premature ignition, unless you are racing full time I would start @ 35 and work up in 2 degree increments until you feel right, you will know by how the bike starts and a couple of hard runs @ WOT in 3rd or 4th gear
     
  8. Breeze3at

    Breeze3at Well-Known Member

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    My Clymer Shovelhead manual has these numbers.
    '66-'69 point gap .020", dwell 90° @ 2,000, Retarded 5° BTDC, Automatic (not advance), 35° BTDC.
    '70-'78 point gap .020", Retarded 5° BTDC, Advanced 34°-36° BTDC.
    Late '78-'79 ignition timer air gap .004"-.006".
    1980 on, Electronic, no adjustment.
     
  9. dynarider

    dynarider Member

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    NICE! Thanks for the numbers. A good source on the XLForum says to try a
    1980-1982 ignition because it's a bolt in for electric start '71 +up. No VOES, no rev limit, and low speed retard for the starter.

    I wonder what Screamin' Eagle ignition modules would retrofit to a '72 Sporty, anyone know?
     
  10. dynarider

    dynarider Member

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    Would a module p/n 32436-91A work if used with a VOES?