Piston Arm?

Discussion in 'Motorized Bicycle General Discussion' started by MrLarkins, Jun 23, 2008.

  1. MrLarkins

    MrLarkins HS Math Teacher

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    Question 1: What is this part called?
    [​IMG]
    Question 2: Mine has about 3 to 5 mm play left to right, is that normal or excessive?
     
  2. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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    Rod. Piston rod.
     
  3. MrLarkins

    MrLarkins HS Math Teacher

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    is it suppose to be tight, or have some wiggle to it?
     
  4. misteright1_99

    misteright1_99 New Member

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    The technical term for it is "connecting rod"..
     
  5. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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    Supposed to move with the piston, but have very mininal side to side movement....what ya mean by "wiggle"?
     
  6. MrLarkins

    MrLarkins HS Math Teacher

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    by wiggle, i mean side to side movement...about 3mm to 5mm
     
  7. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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    5mm Sounds like a lot - I don't know what the spec is - PM Norman to check this thread!
     
  8. Norman

    Norman LORD VADER Moderator
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    I have no specs. on these engines but I'm guessing you should be ok. You don't see any metal flakes or metalic particles inside the crankcase do you?
    That would be caused by a needle bearing trashing on either the wrist pin or on the crank end of the rod.
    what you had outlined in red is the wrist pin end of the connecting rod.
    You will have some side to side play on both the wrist pin end and the big end of the rod and as sorry as these engines are made probably some circular twist as well.
    It looks like either you have a needle bearing wrist pin or else you pressed out the writ pin bushing.
    Are you having a problem or hearing a strange noise with this engine?
     
  9. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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  10. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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  11. MrLarkins

    MrLarkins HS Math Teacher

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    beast...hehe, it sure is making me work hard for my pleasures!
     
  12. Norman

    Norman LORD VADER Moderator
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    did you put the same thickenss base gasket on as you took off that will affect the timing of the ports but it should still run better than what its doing now?
    On some of your pictures of your engine apart I see somekind of black goo inside the engine. I'm wondering now after hearing it run on the video if you have a mainseal leaking on the crank? something is off and thats for sure. Have you checked you rotor on the ignition side to make sure the key isn't sheared?
    It make me think that your needle in the carb has worn strangly out of taper but thats anothe hip shot. You do have a problem though
    I'm still wondering if you have the one piece flywheels or the bolted ones?
    well there some things to think about.
     
  13. MrLarkins

    MrLarkins HS Math Teacher

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    i can take a picture or video of whatever you'd like to see...just name it (or better yet, describe where its at...cause I don't know where this stuff is at)
     
  14. Norman

    Norman LORD VADER Moderator
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    can you contact your seller and ask him if the flywheels are one piece or is there weights bolted on the flywheel? They may not know and I've not taken one apart with the built up flywheel so I don't know if you can tell by pulling off the head and cylinder. but that shaking makes me wonder?!
    You might ask Mr. Dax he might have some insite on this.
     
  15. MrLarkins

    MrLarkins HS Math Teacher

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    i got it from kingsmotorbikes.com
     
  16. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    If the engine has only 150 miles why don't you have them replace it?
     
  17. MrLarkins

    MrLarkins HS Math Teacher

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    i hadn't tried that...guess I'll call Mark from KingsMotorbikes.com
     

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