slant head vs regular

Discussion in 'Motorized Bicycle General Discussion' started by Dougan, Jun 24, 2011.

  1. Dougan

    Dougan New Member

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    I'm just curious, I have a 66cc slant head grubee skyhawk on my bike that has a standard finish (and is covered in oil) and I also have an extra engine (66cc, I think it's a PK80 but not sure) that is not a slant head but has the nice black finish to it. I'm considering on swapping the current motor out with the black one but I'm worried about power loss. How noticeable is the difference between slant and non-slant?
     
  2. dmb

    dmb Active Member

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    i'd say a good ngk plug and wire would make a bigger difference. slant head's mostly for clearance
     
  3. DuctTapedGoat

    DuctTapedGoat Active Member

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    People say the slant head has more compression.
     
  4. Al.Fisherman

    Al.Fisherman New Member

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    Never had a regular head, all have been slant. Oil...ummm is it from the spark plug hole or between the head and cylinder. Between the head and cylinder is a sign of head gasket leak. Remove head and mill it down. If the gasket is good, spray with kopper kote and see if it can be used again.
     
  5. Dougan

    Dougan New Member

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    The oil was because I had the wrong muffler and it had too much back pressure which forced oily exhaust out of the gasket. Its fixed now, not a problem. Just like the look of the black finish better, that's all. Anybody else that can wweigh in on slant head vs regular?
     
  6. The_Aleman

    The_Aleman New Member

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    All 5 of my 2-strokes had the regular non-slant heads on em. Ran fine as far as chinagirls go. If you're worried about any power difference, bolt the slanthead on the older engine.
     
  7. DuctTapedGoat

    DuctTapedGoat Active Member

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    I can weigh in on something else - black painted motors.

    A common issue is that they get WAY too hot, I wouldn't ever run one - but also, I do computer work all day long. When there's a colored heatsink, it's because the metal is annodized, not painted - and with good reason.
     
  8. Scootershack

    Scootershack New Member

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    Oil...ummm is it from the spark plug hole or between the head and cylinder. Between the head and cylinder is a sign of head gasket leak.[/QUOTE]

    what if it is from the spark plug hole? I have some from there. What does that mean? To rich of fuel/oil mix?
     
  9. rustycase

    rustycase Gutter Rider

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    There's a couple of nice threads here about how to lap a head on some fine sandpaper to improve it's ability to seal...

    And if the sparkplug seal is leaking that much, someone was probably too heavy - handed when tightening the plug. My cystal ball sees a helicoil in the future. :)
    rc
     

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