Bike Running Horribly

Discussion in '2-Stroke Engines' started by Bike running horribly, May 8, 2016.

  1. I got a motorized bicycle off eBay a couple months ago and ever since then I've had nothing but trouble and problem after problem with it so it's become my hobby pretty much repairing it to the point it's almost solid and running the way it's supposed to but a couple days ago I went to get on it the next morning and the performance was horrible barely any throttle response and my speed is usually around 24 mph or so I think although I was told the top speed would be around 40 mph but yeah now when I ride it it goes very slow like maybe 7 or 8 mph at full throttle and won't accelerate any further the carb floods or something when I ride it won't idle the choke vibrates up very easily making it even slower until I notice and flip it back down where it regains a tiny bit of power I might have tighten that up hills are awful the engine pretty much dies if I stop pedaling up a hill I've checked a bunch of things but I'm at a loss now I've Opened the inside of the carb and inspected it for dirt damage being stuck things like that and it looks perfectly clean in there any more information id be glad to share I just want the performance fixed because it's my only transportation and it's eating through gas this way
     
    Alexmeow likes this.

  2. FurryOnTheInside

    FurryOnTheInside Active Member

    Does it have oil or smoke coming out anywhere?
     
  3. FurryOnTheInside

    FurryOnTheInside Active Member

    Air
    Fuel-oil
    Carburetion
    Compression
    Spark
     
    Last edited: May 9, 2016
  4. James L

    James L Member

    My bike ran similar to that... It would run really slow and surge alot. Not sure if yours is doing that same thing or not but as funny as it sounds mine was loose motor mounts. The carb flooding not sure, i i did take the bowl off on the carb and clean it out using a bread tie wire.. Old trick i learned from a guy who owns a motorcycle repair shop. The choke lever if your bike is like mine and has the black air filter i removed mine and tightened the nut on the choke and problem solved as far as the choke lever.
     
  5. Alexmeow

    Alexmeow Member

    I don't think it's smoking but everytime I stop the bike black hot liquid drips out onto the pavement that might be the oil. That's what I mean by the carb flooding because it doesn't leak when it's off only when it's been running.
     
    Last edited: May 9, 2016
  6. FurryOnTheInside

    FurryOnTheInside Active Member

    Black hot oil? Burnt oil? So look for a leak at the place where oil is burned, the head: gasket, spark plug. Clean the engine especially around the top of the cylinder and the whole cylinder head, then see if you can find where the black hot oil actually comes out. Could be the head just isnt tightened up tight enough.. They do need retightening. Do you have a torque wrench? Might not have to look elsewhere or disassemble anything.
     
  7. Alexmeow

    Alexmeow Member

     
  8. FurryOnTheInside

    FurryOnTheInside Active Member

    That's what I said. ;)
     
  9. Alexmeow

    Alexmeow Member

    The stuff that drips down is usually in a pool under the carb even though I have it tightened really well and drips onto the ground and it's black I don't even know where it would be leaking from on the carb I've felt under the air flow holes on the nt carb and it's got some gas on it and when I took it apart to clean the air filter with water there was definitely gasoline all over it
     
    Last edited: May 9, 2016
  10. Alexmeow

    Alexmeow Member

    I'm starting to think maybe it's an electrical problem like the spark plug or the cdi because the insulation on it is stripped almost all the way on the connection part exposing the wire at the base of it and maybe the weak spark isn't burning all the gas properly and causing it to flood? The spark plug is a darker color looks kind of burnt
     
  11. FurryOnTheInside

    FurryOnTheInside Active Member

    You really weren't kidding in the title were you?
    Well it is always possible your engine has multiple problems. You can only investigate and fix as you go. But don't worry, it'll be fine. Just start with the easy and free stuff that's why I said get it clean on the outside so you can hopefully spot the source of that black hot oil. Looking at it costs nothing.
    Clean the air filter and see if it gets better, that's the next easiest thing and it's free too, also see if it stays clean or the problem comes back. Having the air filter blocked so the engine can't breathe and get oxygen would cause problems with combustion of the fuel so why even look at the cdi that can only be fixed with $$ do the easy and free things first.
    Of course insulate your wires with some electrician's tape or whatever you like.
     
  12. Frankfort MB's

    Frankfort MB's Well-Known Member

    First off, a stock bike won't run but about 20-25mph
    Second check your spark plug to see what color it is and if it's wet
    Third check the baffle at the end of the exhaust since it might have filled up with oil and it would cause the bike to have too much back pressure
    If none of the above works then make sure that there isn't oil in places there shouldn't be (aka, mag cover... Clutch cover.... )
    And what are you mixing your oil:gas at?
     
  13. Steve Best

    Steve Best Active Member

    Furry and Frank have it right, check these things one at a time:
    Air - No air leaks? filter clean? choke opening all the way? bolts tight on the manifolds? carb on tight? Base gasket not leaking?
    Fuel-oil - is it getting gas? is your mix at 32:1?
    Carburetion - is the float level correct? Jets clean and tight? (it was working right?)
    Compression - no leaks from the head gasket whe it runs? (feel with your hand) noticable resistance when you turn the motor over?
    Spark - try a new spark plug? gap right? heat range right? (try a hot one if all else fails) put the bike on a stand and see what you get for spark?

    Black goo dripping says too much oil or too rich mixture. Black plug says the same thing. 100ml oil in 3.2 L of gas. No more oil. Less is better.
    Cheap oil? Do you have enough spare time in life to mess with this? Buy the best oil, mix 40:1 or 50:1 and forget what a fouled plug is.
    Go over the bike from top to bottom, tighten everything, check everything.
    If it worked good yesterday, there is only one thing wrong. Don't modify everything.

    Steve
     
    Timbone and Frankfort MB's like this.
  14. Frankfort MB's

    Frankfort MB's Well-Known Member

    One peice at a time as Johnny Cash always said ;)
     
  15. Alexmeow

    Alexmeow Member

    I try to keep the gas mixed in between 32:1 and 16:1 sometimes I just pour some oil in with the gas but I have a gas can that I mixed at 16:1
     
  16. Steve Best

    Steve Best Active Member

    You are creating your own problem.
    Mix your gas at 32:1 and your problems will go away. You are using WAY TOO MUCH oil. Less is better.

    Steve
     
    Timbone likes this.
  17. Alexmeow

    Alexmeow Member

    Wow thanks a lot for all the replies I don't have a job at the moment so fixes that cost money are a bit iffy so I'll take your advice and go over all of it tomorrow and see if I can figure out just what's going wrong
     
  18. Alexmeow

    Alexmeow Member

    So I should just let it run until the gas in it right now is up than re fill it with a higher ratio of gas and that will fix it ?
     
  19. Steve Best

    Steve Best Active Member

    No.
    Drain the gas you have in it right now.
    Buy a very good quality "premix" oil, I prefer Motul or Ipone. 1 Litre will last all summer.
    Mix the gas in a jug at 32:1 (or as little as 50:1 with the above oils) and run it.

    You will be amazed at the difference. Great starting, long plug life, POWER.

    If you futz with the gas you have in the tank or cheap oils you will continue with the same problems.

    Steve
     
  20. Alexmeow

    Alexmeow Member

    I went to start it today after putting new gas in and the engine wouldn't turn over for a while I had to keep pedaling and releasing the clutch and it wouldn't turn over for a bit and when I stop the ending and try riding it again the same thing happens so I guess I can add hard starts to my list of problems and I turned the fuel petcock off and right before it ran out of gas it picked up speed to where it was supposed to be for just a second then I put it back on and it went back to the same slow performance it seems like it's flooding out of the drain screw the idle speed screw anywhere there's a hole kind of I took off the carb and shook it around and it seems to leak the most out of the air filter
     
    Last edited: May 10, 2016
Loading...