New 4-stroke King Motor Bikes G-8 with maybe 3 hours on it lost 80% of it's power.

Discussion in '4 Stroke Bicycle Engines & Kits' started by Harry Coddington, Sep 5, 2019.

  1. Harry Coddington

    Harry Coddington New Member

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    I posted about this in another forum here, but wanted to share here too, as I really need my bike back on the road as quickly as possible.

    I just installed this 49cc on my 26" beach cruiser 5-speed after my last engine seized-up and died. I rode it around my street the first night I put it in and it was amazing how strong and fast it was.

    I took it out the next day for an hour or maybe 2 at the most and noticed as I was riding it, the power level was getting less and less as I rode. It barely made it up the hill on my street by the time I got it back.

    I cleaned out the jet on the plastic thing underneath the idle screw with carb cleaner and a guitar string, but it's still very weak and absolutely nothing resembling the first ride I took it on. I noticed that the air filter was soaked with gas and it appeared like the oil I drained out of it was thinner, very black and smelled like gas, but I could be mistaken about that part.

    I've tried to call Kings Motor Bikes but nobody ever answers their line and the hold line cuts you off after 5-6 minutes, so I have nowhere to turn about this.

    I have a couple other 49cc motors that are dead, but have good parts(carb, transmission, head, exhaust, pull start) and can replace some parts, but am just dumbfounded about this, as I figured a booger in the jet would be the problem as it's acting like a fuel issue.

    Please help!
    Harry
     
  2. Apache Bronco

    Apache Bronco New Member

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    Would a stuck ring do this?
     
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  3. Greg58

    Greg58 Well-Known Member

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    Sounds like the float is stuck open filling the engine with fuel, disassemble the carb and clean it or replace it.
     
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  4. Harry Coddington

    Harry Coddington New Member

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    So, I took the carburetor apart cleaned it all...jet, bowl, float and all of the structures and put it back together and it still was the same.

    I found a video and also took apart the transmission and the belt is still in new condition as well. I couldn't figure out how to get the clutch out(the video I found is about the 7G and mine is the 8G, and the clutch assembly and little gear is different than the 7).

    I still am completely puzzled with this thing!

    Anything else this could be?

    I'm serious that this has only a couple hours tops and it was running stronger than my original 49cc Bike Berry kit with the metal transmission housing ever did, then it just got weaker and weaker to where I can barely get this thing up my street. Please help me out if you can.
     
  5. Greg58

    Greg58 Well-Known Member

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    Try removing the muffler end cap and do a test run, could be a stopped up muffler.
     
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  6. Greg58

    Greg58 Well-Known Member

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    Change the carburetor next, did you check the float? Still sounds like gas is running into the engine.
     
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  7. Harry Coddington

    Harry Coddington New Member

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    Thank you for your response, Greg, as well as everyone who has responded to my thread.

    I thought the same about the float, but I don't see any more gas in the air filter since I've taken the carburetor apart and cleaned it all thoroughly(jet, bowl and float especially) and I'd ridden it a few hundred feet in front of my house back and forth and it still was acting like a pig.

    I changed the oil again and it wasn't as dirty and as thin viscosity it was after the first oil change(then, it was black and thin as all getout and smelled heavily like gas) and put in 0.20 L.of 10W-30.

    I took it out in front of my house again and the results are the freakin same. Runs like a pig and doesn't even remotely resemble this bike when I first put this kit on it.

    I'm getting fried, trying to figure out what is up with this simple little engine... ugh
     
  8. Greg58

    Greg58 Well-Known Member

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    Have you tried cleaning and gapping the spark plug? Maybe try a different one. You probably need to check the compression next.
     
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  9. Harry Coddington

    Harry Coddington New Member

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    I checked the gap and it was right on. I replaced the carburetor, changed the oil again(still smells gassy, but that could be residual leftovers), even switched the transmission to the old belt drive one and it made absolutely no difference whatsoever.

    Do you know if there are any service manuals for these motors/kits? I'd like to check valve clearances, but don't know what they're supposed to be.

    Another question is has anyone ever gotten through to customer service at Kings Motor Bikes? I've tried to email and got no response. I tried to call and it seems their hold line will keep you on there for 5 minutes then just hangs up on you. Everything I've done to get in touch with them has been a dead end.. Funny, they sure jumped on it when I was purchasing this thing. My kit came in a beat-up box without even a manual in it. It had my address tag and a packing list. That was it!

    I just know I couldn't have killed this thing in this short of a period of time! Jeez, I was watching it and there was no smoke and it wasn't getting extremely hot, if just got weak gradually as I rode it! \

    Man, someone please help me out with this. I'm starting to really feel like I got suckered.
     
  10. Greg58

    Greg58 Well-Known Member

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    I would check the compression first.
     
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  11. Harry Coddington

    Harry Coddington New Member

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    Greg, do you know what the compression is supposed to be? Ballpark?
     
  12. Greg58

    Greg58 Well-Known Member

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    Usually 90-100 psi or more will run good.
     
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  13. Harry Coddington

    Harry Coddington New Member

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  14. Harry Coddington

    Harry Coddington New Member

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    Do you know any way to get ahold of kingsmotorbikes? I've emailed them, and have called so many times, I'm pissed off at their phone system. I get put on hold and every time at about 5 minutes, it automatically hangs up on me.

    My original kit was from bikeberry and those guys are there to try to help, at least.

    This is getting ridiculous.

    I left my bike in my brother-in-laws garage, so I'll do the compression test tomorrow and see what that tells me, if anything at all...
     
  15. Harry Coddington

    Harry Coddington New Member

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    OK compression was 110 to 115 consistently.

    Can anyone tell me what the valve clearances are?

    I cannot find specs for these motors anywhere.
     
  16. Harry Coddington

    Harry Coddington New Member

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    Is there a service manual available for these?
     
  17. Harry Coddington

    Harry Coddington New Member

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    Thanks again, Greg!

    You're never going to believe what it was....

    The end of the pushrod, on the intake side, had come out of the ball cup on the rocker arm!

    It's running like a bat outta **** now, but it's idling kinda funky, so there's a bit more to be done before I jump on for a victory ride, but who on this planet would ever have thought of that?

    There's one for the books!

    I'll keep posting updates and put a picture or two of the old girl! She's a black, '79 Chicago Schwinn Cruiser 5. I still have the 5 speed rear wheel that's a real clunker! Heavy spokes! I've got the old-school paperboy side-bag-style baskets for grocery-gettin' and such. She ain't super pretty, but she kicks! This one had the original 49cc motor with the chain-drive transmission and I've put almost 2000 miles on this bike in the months in Maine I can ride. I put an analog speedometer on it after about 400-ish miles!
     
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  18. indian22

    indian22 Well-Known Member

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    That would explain it & tear down is often the only course of action to follow & saves time as well.

    Glad you've solved this problem.

    Rick C.
     
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  19. Harry Coddington

    Harry Coddington New Member

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    I've been riding it quite a bit lately and it seems to run very well, but maybe not as strong as that very first ride, but I'm assuming it's just broken-in, but don't get me wrong, this thing is definitely a step-up from the old, chain-drive transmission that was a 10-tooth sprocket, this 12-tooth, belt-driven transmission is not only quieter(especially now with out the little pushrod knock), but it's definitely got more top-end speed. I use the standard 44-tooth rear sprocket(I have a few of them-36, 40 and 48 and a bunch of 44's).

    I did notice that the large pulley of the transmission wobbles a bit, like it wasn't installed correctly fro the getgo. It came already with the black cover on it, but I guess I should have checked. I've got to see if I can straighten it, as I bet it'd feel a whole lot better and give me more years out of those bearings..
     
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