arrow on piston

Discussion in 'Motorized Bicycle General Discussion' started by crassius, Sep 24, 2014.

  1. crassius

    crassius Well-Known Member

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    got in some kits today with top end removed

    put 4 together so far & found 2 with piston arrow pointing forward & 2 with arrow pointing back (with locating pins on intake side)

    all from same supplier, all seem same as far as other h/w goes, all machined cranks

    the point: never look at the arrow (if it has one)
     
  2. Greg58

    Greg58 Well-Known Member

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    I never look at the markings for piston oreintation, I have found as you have they don't always mean the same thing. Installing the piston with the ring end pins toward the intake is what I do also. The one thing I have learned is never assume anything, check for yourself!
     
  3. 2door

    2door Moderator
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    I have found the same thing from the same supplier. I concure about ring orientation. That's more important than a little arrow stamped into the piston.

    This is one of those inconsistancies like carburetor jet sizes. I've found them to be nebulous. I never rely on the advertised/stamped or published size. Actually checking the orifice size is the only way to be sure of what you have.

    Tom
     
  4. crassius

    crassius Well-Known Member

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    Yeah, I see a lot of diff markings at the shop, but this is first time with all in one delivery.
     

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