got my first chinese 50cc kit - need advice

Discussion in 'Motorized Bicycle General Discussion' started by Mike Hunt, Jun 9, 2009.

  1. Mike Hunt

    Mike Hunt New Member

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    Just picked up a Chinese 50cc motorized bike kit from this Chinese guy on the other side of town. I have a bike I'm planning on using but first i'm going to replace its non-suspension front fork with one that does have off an older bike i have. Im also going to put new brakes, possibly tires, tighten everything up, etc.

    Is there anything i need to know before i start mounting the kit?
     
  2. Cabinfever1977

    Cabinfever1977 New Member

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    make sure you have clearance for the peddals,muffler and intake with air cleaner before tightening everything fully or adjusting chain or modifing anything. put tape on the frame so you dont scratch it up when you try the engine on the frame.
     
  3. reg454

    reg454 New Member

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    duel pull brake lever will do you a lot of good.
     
  4. Mike Hunt

    Mike Hunt New Member

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    how do you use the clutch lever and throttle on these moped kits? is it the same as what i would expect on a motorcycle or the function different?
     
  5. Goat Herder

    Goat Herder Gutter Rider

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    works like a moped peddle assist . When you let the clutch out be peddling! You are first gear. Also when starting it up peddle all the way through starting it. Get momentum going before you let that clutch out. Welcome to the forum Biker!
     
  6. Cabinfever1977

    Cabinfever1977 New Member

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    like a motorcycle but cheaper.
     
  7. Mike Hunt

    Mike Hunt New Member

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    alright so the moped is almost done (or is it?), just gotta attach the chain, fuel line, clutch cable, and attach the twist throttle to the handle.

    couple questions:

    1) i haven't put any kind of lube anywhere (other than the parts that were already on the bike), what is the proper way to do this?

    2) when i first got the motor, i pushed the lever on the motor that controls the clutch all the way in, and was able to turn the sprocket by hand, although i could feel a lot of resistance, when i let the clutch lever spring back to its original position, i tried to turn the sprocket by hand and it wouldn't budge. is this what is supposed to happen?

    3) what else do i need to do before i can fire her up for the first time?
     
    #7 Mike Hunt, Jun 21, 2009
    Last edited: Jun 21, 2009
  8. Cabinfever1977

    Cabinfever1977 New Member

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    answer for #2 is yes thats correct,and you dont have to use the spring,it will be easier to use clutch without spring.

    and for #3 check everything twice,make sure tensioner is tight,walk bike around and make sure chain doesnt jump off.make sure wires doesnt touch muffler.
    only go for a short ride at slow speed til you know everything is good.
     
  9. Mike Hunt

    Mike Hunt New Member

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    is the chain tensioner really necessary? it seems like i could get away without it, and im kind of nervous that if it gets loose it might just flop into the spokes and make a huge mess of me and the bike.

    also i would really like a pull or kick start for the engine instead of having to pedal start, whats a good place where i can get one, preferably the kick start (for no other reason except that i think it would look cooler).

    one more thing, where do i connect the kill switch?
     
    #9 Mike Hunt, Jun 21, 2009
    Last edited: Jun 21, 2009
  10. Finfan

    Finfan New Member

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    I've heard of people who adjusted the chain close enough using half links to do away with the tensioner. I am still looking for a good replacement. That part worries me to!

    You should be able to find a pull start on ebay or from one of the dealers that advertise here. I've never seen a kick start for the Chinese engines.

    The kill switch is a momentary closed type switch. You can either wire it between the two wires that run from the engine to the CDI or else from the white wire to ground. Usually it is best to attach it directly to the engine case for ground. Either way when you hit the switch it kills the spark.

    Good Luck!
     
  11. reg454

    reg454 New Member

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    well if you want to spend some money you can get a jack shaft kit from sick bike parts,it lets you kick start and also lets you use the gears on the right side of the rear tire and not have to use the big sprocket and chain tensioner. the kit is like $200ish
     
  12. Mike Hunt

    Mike Hunt New Member

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    im not sure if i did this right, i connected the black wire from to the motor to the black wire on the CDI, and the blue wire from the motor to the blue wire on the CDI. one of the wires on the kill switch i connected to the white wire coming off the motor, and the other wire on the kill switch i connected to the engine case by slightly loosening the white knob that has the three wires going through it, sticking the wire in between the knob and the engine case for the ground.

    everything else is assembled, and hopefully ready for a test run.

    do i need to put any lube inside any of the engine components?

    also, when i have the clutch disengaged the bike rolls fine, but when its engaged it locks up the wheel when i try to push it , but if i turn the rear wheel by hand it turns the sprocket inside the engine and i can hear sort of a clackety sound, is this good or bad?
     
  13. Cabinfever1977

    Cabinfever1977 New Member

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    i would use a bolt or screw for the ground or atleast tape it on.
     
  14. Mike Hunt

    Mike Hunt New Member

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    its wedged pretty tight in there, not going anywhere. once i make sure the engine runs im gonna go over all the fasteners again and double bolt everything.
     
  15. Mike Hunt

    Mike Hunt New Member

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    is there any way to check that the spark plug is working properly without actually firing it up?
     
  16. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    Pull the plug out, re-attatch the wire, ground the plug to the engine, and turn the rear wheel.

    Might need a helper.
     
  17. Mike Hunt

    Mike Hunt New Member

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    yay got her to run. fueled her up at 20:1, went down a hill, popped the clutch, engine turned over trying to start, but as soon as i disengage the clutch it died on me. got it to start with choke about half way up, but still dies after about 10 seconds unless i keep revving it. after i got it started i kept revving the engine at up to half throttle with the clutch disengaged for 10 minutes. let it cool for about an hour, then took it for a ride in front of my house staying below 3/4 throttle, but i did open it up a couple times very briefly. it died on me a couple times though when i was turning around and i forgot to keep revving the engine.

    what is the proper way to adjust the choke and the idle screw so it doesn't die on me?

    i also noticed a little bit of fuel on top of the carb where the primer button is located, is this a leak or is it because i primed it too much, after the second run the spot of fuel didnt get any bigger, so i figure its because i primed it too much, but im still a n00b at this, so i cant really know for sure.
     
    #17 Mike Hunt, Jun 28, 2009
    Last edited: Jun 28, 2009
  18. reg454

    reg454 New Member

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    Take your spark plug off and look at the color of it, what is it brown black white? If the color of it is white you are running to lean that is you motor starving for fuel,if it is brown your perfect, if it is black you are running to rich that means too much fuel. you can adjust how much fuel you motor is getting by where you have the c-clip on the needle that is inside your carb on the slide you move it up to get more fuel and move it down to get less fuel only move it one notch then test your bike at WOT for a minute or two then kill your motor let it cool then check your plug again.

    How much do you have the idle screw turned in?

    If you close the choke all the way does the motor die if it does not your intake has a major air leak either where you mount the flange to the motor, where you put the carb on or both. If you do have an air leak you can use some black or orange rtv gasket maker stuff to fix it. When you put it on the part that the carb goes on try not to have any of it on the end but around the pipe also let the stuff dry completely or most of the way for a perfect seal.
     
  19. Mike Hunt

    Mike Hunt New Member

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    i checked the spark plug after the first ride and its a very dark brown. on the second run, shortly after i started i moved the choke all the way down and it died.

    my fuel line is rather long, and there's a about two inches of fuel at the very bottom, then 2 inch bubble and another 2 inches of fuel followed by another bubble that goes all the way into the tank. is it supposed to be fuel all the way through?
     
    #19 Mike Hunt, Jun 28, 2009
    Last edited: Jun 28, 2009
  20. Mike Hunt

    Mike Hunt New Member

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    is the choke supposed to be in the fully closed position during normal operation?

    i took it for another ride and after warming it up a little and playing around with the choke and idle screw it idles a little while but still dies if i don't keep revving it a little bit. perhaps if i tighten the throttle until its open about 1/16 of the way at the fully closed position it'll take care of my dying while idling problem?

    this thing is sooooo much fun tho, acceleration is really slow without pedaling, but at half throttle uphill it goes about as fast as i bike on level ground, pedaling vigorously, which is i find quite satisfactory.

    this is my first motor vehicle btw


    cflg
     
    #20 Mike Hunt, Jun 28, 2009
    Last edited: Jun 28, 2009

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