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  1. #1
    philip_gpr's Avatar
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    Pistonwash Pictures - Opinions wanted





    Last edited by philip_gpr; 09-02-2006 at 04:16 PM.


  2. #2
    philip_gpr's Avatar
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    Stock 1200 motor using a set of stock 1300 cylinders, FAs, CDI, reeds

    stock carbs with this jetting
    110
    130
    1.5 / 95

    The black you see in the pictures is very dark and thick

    So which circuit is rich and which circuit is lean????

    What is surprising is the motor is running great - best is 14/20 Dynafly with 85 mm at 7350.

  3. #3
    Quote Originally Posted by philip_gpr
    Stock 1200 motor using a set of stock 1300 cylinders, FAs, CDI, reeds

    stock carbs with this jetting
    110
    130
    1.5 / 95

    The black you see in the pictures is very dark and thick

    So which circuit is rich and which circuit is lean????

    What is surprising is the motor is running great - best is 14/20 Dynafly with 85 mm at 7350.
    Philip, how far your top screws turned out?

  4. #4
    philip_gpr's Avatar
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    mains were at 3/4 turns

  5. #5
    I'm no expert but they look good to me. #3 is a little rich but better safe than sorry.

  6. #6
    xyzyx00's Avatar
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    has that motor allways been running the same setup, has jetting/ new bolt ons changed recently?

  7. #7
    HopatcongGPR's Avatar
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    the black carbon is a burn cycle from a lean circuit.

    its washed out by the transfers because the last run cycle was mainly in a richer circuit.

    the center portion of the crown should be a caramel color with wash around the perimeter. black is oil burned on the crown from the flame front/combustion cycle occuring directly on the crown. if its caramel you have the correct fuel mixture; ie., boundry layer in which the flame front/combustion process occurs on keeping the piston crown cooler/caramel color.

    if you pull one of those pistons i GUARANTEE it has a big black spot centered under the crown.

    my guess is the 130 is OK, the 110 is lean (go 112.5...probably need 115). the 1.5 should go to 1.8 or 2.0 with the same spring (95) to start. you may want to check the pop off with the 95/1.5 setup and match the 2.0 setup accordingly IF the pop off feels OK. the 2.0 and the 115 will help the 3/8-1/2 area. the 2.0 will increase fuel volume IF the demand requires it (3/8-1/2 throttle area/ transition circuit).

    AND, dont be afraid to stagger the jetting. 1 looks ever so slightly hotter then 2 and even more hotter then 3. my guess is at the end of the day 3 could/will be one jet leaner then 1 and 2. but i wouldnt mess with staggered jetting until i got the black carbon caramel. but thats just me.

    hope that helps and it just my opinion.

  8. #8
    mtrager's Avatar
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    Phillip, by going to 2.3s on my triple it made a world of a difference.

    Color is everywhere on the plugs and has alot more snap in the midrange.

  9. #9

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    Cool thanks for the reply will check out the usual culprits

  10. #10

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