How do you tell what CC engine you have?

Discussion in '2-Stroke Engines' started by Taylor20001, Sep 19, 2011.

  1. Taylor20001

    Taylor20001 New Member

    Hello, I have a new used Schwinn with a motor on it but know idea what CC it is, so I can start buying parts for it to tweak it out. So how do you tell ???

  2. adrian101

    adrian101 Member

    upload a photo of the engine and i should be able to tell you just by the size of it.
  3. FelipeCobu

    FelipeCobu Member

    Normally if you have a found head and jug it's 49cc.

    But square head and jug can be 66 or 69 cc

    Best way to know it is to remove the head and measure the bore and stroke and do the math.
  4. HeadSmess

    HeadSmess Well-Known Member

    48 have 10mm nuts on m6 studs

    66 has 13mm nuts on m8 studs.

    studs are (from memory)

    39 mm apart on a 48,

    45mm on a 66. measured "square" not diagonal...

    other external differences are minor... 48 has smaller thicker fins...? 66 is wider in the cylinder etc...

    if you pull head off,
    48 has a 40mm piston,

    66 is 47mm
  5. MotorBicycleRacing

    MotorBicycleRacing Well-Known Member

    It is not quite that simple, so measuring between the head studs
    is the best way to know which motor you have.

    The 66 cc Grubee Starfire motors have 6 mm head studs.
    along with other non branded motors from NaiTong JaiLi

    The new 66 cc Grubee rat motors have 6mm head studs too.

    50 cc motors come in round and square head.
  6. Taylor20001

    Taylor20001 New Member

    Here are the pictures of the engine

    I hope by seeing these you can tell what CC it is.


    Attached Files:

  7. Taylor20001

    Taylor20001 New Member

    In need of a gas cap cam off on the way home

    I have take a pick of the gas tank because I have lost the gas cap. the size is 1 1/4 for the part that goes in the tank and the ears that stick out are 1 3/8 across. If any one has one or knows were to get one please reply.:detective:
  8. adrian101

    adrian101 Member

    It looks like a 66cc engine from the photo. Measure between the head nuts (photo below of what im talking about)

    If it is a 66cc engine the distance between the nut is 45mm apart.

    You can get gas tank lids from ebay for cheap, just type (motorized bicycle gas tank caps) What country are you located in?

    Let us know what the distance is between the nuts asap.
  9. Taylor20001

    Taylor20001 New Member


    Hello, do you know what that is in inches??? USA Texas North Richland Hills area.
  10. adrian101

    adrian101 Member

  11. Taylor20001

    Taylor20001 New Member

  12. IbedaYank

    IbedaYank Member

    looks like a 66cc with the head leaking
    gonna have to fix that and get the head/cylinder flat/square and replace the POS factory studs with grade 8 has the studkit
  13. Taylor20001

    Taylor20001 New Member

    Finding parts

    I thought that looked like a leak but were do you get a head gasket, can i make one I have a full shop.
  14. IbedaYank

    IbedaYank Member