Engine Trouble Wont start, tried everything.

Discussion in '2-Stroke Engines' started by daobs99, Jul 8, 2015.

  1. daobs99

    daobs99 New Member

    Hey guys, the other day my bike stopped working. I didn't use it for about two weeks and when I tried to again it would not start. I replaced the spark plug with an NGK, I changed the carby, fuel line, fuel filter, and CDI Assembly. It still wont start. When I release the clutch the engine makes normal noises as if it is trying to start but it wont turn over. I've kept pedaling for about a minute and I've started it downhill, but I wont get anything, its really frustrating.

    I bought the bike used and it always had a little trouble starting up cold. I would have to start it with the air intake on the carb all the way open, idle for 30 seconds, then adjust it after. Also it only worked without an air filter. I can't see any reason for it not to start at all now. I'm running a 20:1 fuel ratio also.

    Any help would be greatly appreciated, thanks.

  2. crassius

    crassius Well-Known Member

    I'd first check to see if there is spark at the plug, then check if plug gets wet with fuel when cranking it over - I'd also go to a 32:1 mix on fuel too
  3. daobs99

    daobs99 New Member

    Okay, tomorrow I will try that.
  4. Leroybrown420

    Leroybrown420 Member

    If you have spark and a dry plug. There is a good chance that your carb jet is plugged. Are you using the choke?

    No spark, wet plug then you most likely have a ignition failure. Check the solder connection on the magneto. They will occasionally vibrate loose.
  5. daobs99

    daobs99 New Member

    i'm getting a spark and the plug is dry. I'm always adjusting the choke but I replaced the carb. How do I check if it is plugged?
  6. Leroybrown420

    Leroybrown420 Member

    Pull the carb, pull the float bowl. Unscrew the jet hold it to the light. You should be able to see light at the other end. Also check the fuel inlet for restrictions.

    Last edited by a moderator: Dec 15, 2015
  7. Leroybrown420

    Leroybrown420 Member

    Make sure you have fuel getting to the carb. Some bikes have in-tank filter/strainers that will plug up too. The photo below was a MB with crap in the tank and no fuel filter, everything in the carb was plugged sold. It runs great now.

    PART_1435448557928_0627151642.jpg PART_1435443148924_0627151512.jpg
  8. Zackiriyah

    Zackiriyah Member

    Did it work?
  9. daobs99

    daobs99 New Member

    Okay so I had my mechanic friend look at it and he ran through some tests. Apparently there is no spark and the spark plug has an oily residue when I remove it. The spark plug and CDI are new so I assume its the Magneto. Also the front of my engine is very oily and he thinks there may be a leak. Any Ideas?
  10. crassius

    crassius Well-Known Member

    mag is easy to test with any cheap multimeter - seeing LOTS of dead CDIs lately that are new (something going wrong at factory I suspect) - oil at front of motor is usually loose muffler, but could be loose head, or rarely, loose case bolts
  11. KCvale

    KCvale Motorized Bicycle Vendor

    Nice important details daobs99, it sure helps find a solution.

    Old over oiled fuel isn't going to help troubleshooting, and may even be the cause.
    If I was you I'd...

    Drain and dispose of your old fuel including draining the carb and filter.
    Pull the spark plug out and pedal it up and down the street with the clutch released to blow out any gas in the bottom end.

    Get yourself a nice clean if not brand new gas can and put exactly 1 gallon of new premium in it.
    Pour in 4oz (1/2 cup with a clear measuring cup is the easy way) general use 2-stroke oil.
    Shake well for a 32:1 ratio and serve with a dose of fun ;-}

    It may not solve what's wrong, but when you find it fuel won't be an issue and you will see a performance increase from more actual nice new gas and less oil.

    Remember to turn your carb or gas tanks petcock off when not in use.
    Gas evaporates, oil does not, and these engines are a gravity feed open air vent system, fuel will flow.
    Last edited: Jul 10, 2015