What's your most desirable accessory for a China Girl Motorized Bicycle?

Discussion in 'Motorized Bicycle General Discussion' started by biknut, Mar 14, 2012.

  1. GearNut

    GearNut Active Member

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    Re: What's your most desirable accessory for a China Girl?

    High quality bearings throughout.
    Everything else becomes useless when the wrist pin bearing grenades or a crank bearing galls up.
     
  2. biknut

    biknut Active Member

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    Re: What's your most desirable accessory for a China Girl?

    I have to agree with you. The Chinese bearings are crap. I notice the new Flying Horse motors advertise they come with Japanese bearings.
     
  3. Basement Cat

    Basement Cat New Member

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    Re: What's your most desirable accessory for a China Girl?

    A balanced crankshaft is what I want most.
     
  4. biknut

    biknut Active Member

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    Re: What's your most desirable accessory for a China Girl?

    Yeah I think that should be high on the list too, but pretty advanced for al lot of people.
     
  5. Ibedayank

    Ibedayank New Member

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    Re: What's your most desirable accessory for a China Girl?

    working pedal power so when it breaks you can pedal home instead of pushing it
     
  6. motor_bike_fanatic

    motor_bike_fanatic New Member

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    Re: What's your most desirable accessory for a China Girl?

    a tach and a fuel gauge.
     
  7. wayne z

    wayne z New Member

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    Re: What's your most desirable accessory for a China Girl?

    High quality bearings and a balanced crank would make these into a pretty good motor.
     
  8. mapbike

    mapbike Active Member

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    Re: What's your most desirable accessory for a China Girl?

    I agree 100% on the bearings and a better balanced crank assembly.

    I never had one of these engines back when they had the bronze bushing for the upper bearing instead of the caged needle bearing like they do now, but it seems I have read where people had said the engines with the bushings were better balanced, if that is true it seems that maybe removing some material from the cranks counter weights opposite the rod journal might help the balance since the piston/pin area is lighter now than it was with the bushing.....Shrug?
     
  9. thegnu

    thegnu New Member

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    Re: What's your most desirable accessory for a China Girl?

    My shift kit , disc brakes ,custom fuel tank in that order , lol so actually the motor accessories are last .
     
  10. biknut

    biknut Active Member

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    Re: What's your most desirable accessory for a China Girl?

    All the cranks I've checked needed heavier weight on the counter weight side.

    [​IMG]
     
  11. The_Aleman

    The_Aleman New Member

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    Re: What's your most desirable accessory for a China Girl?

    My first HT was a bushing engine back in '06. It was by far the worst engine I had. Very unbalanced, and it grenaded when I tried to hit 30.
     
  12. biknut

    biknut Active Member

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    Re: What's your most desirable accessory for a China Girl?

    Sounds a lot like my X80 motor.
     
  13. mapbike

    mapbike Active Member

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    Re: What's your most desirable accessory for a China Girl?

    Thats good to know, I was just guessing based on something I remember reading on here a long time ago, but then again I may have it mixed up and maybe whoever it was said what you did about needing more weight on the counter weight side.


     
  14. mapbike

    mapbike Active Member

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    Re: What's your most desirable accessory for a China Girl?

    Well, I,ve never had a bushing engine so I have no experience with them, I remember some debate in the past about them and in the midst of one of the debates is where I thought I remembered someone mentioning the '' better balance '' thing, may be hog wash as you sorta said here, I'm glad we have the needle bearing instead on the bushing.

    Peace, Map


     
  15. mapbike

    mapbike Active Member

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    Re: What's your most desirable accessory for a China Girl?

    Biknut, how did you figure out the counter weight side was too light?

    Do you have a homemade contraption to roughly balance the crank assembly?

    Map
     
  16. moonerdizzle

    moonerdizzle New Member

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    Re: What's your most desirable accessory for a China Girl?

    I prefer bushings for one reason. Most bushings slowly fail and let you know "hey! I'm old and wore out . Replace me before I ruin your day."
     
  17. mapbike

    mapbike Active Member

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    Re: What's your most desirable accessory for a China Girl?

    Yeah I kinda figured the worn bushing would start knocking on the top end before it completely failed which would be a fair warning that it needed to be replaced.

    But like I said I have no experience with bushings in these engines so I can't swear to anything concerning how they are/were, I figured they got away from them because they had a very short life in these engines and were causing loads of failures

    Map


     
  18. The_Aleman

    The_Aleman New Member

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    Re: What's your most desirable accessory for a China Girl?

    They might knock stock. HTs don't like being revved too high without some work. From my XP anyway.
     
  19. Texhun

    Texhun New Member

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    Re: What's your most desirable accessory for a China Girl?

    I lost my first two HT's because of those dumb needle bearings on the wrist pin. On my current engine I replaced the wrist-pin needle bearing with a bushing. Mapbike this is by far the best engine I've had! It's smoother and better balanced, this might sound a little off but it's also got way more power too! I run this engine way harder than the first two and it's gone twice the distance of the first two engines combined. I'm all for bushings in these engines. I wanna try doing a crank job on it sometime, seems like it just might be worth it. Just for the guys wondering, it's the K-80 from BGF, the first two were PK-80's also from BGF. Ironic isn't it? rotfl
     
    #39 Texhun, Mar 16, 2012
    Last edited: Mar 16, 2012
  20. mapbike

    mapbike Active Member

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    Re: What's your most desirable accessory for a China Girl?

    Texhun

    Did you machine the bushing yourself?

    Or did you find a source for them?

    Peace, Map


     

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