Engine Trouble bike wont start

Discussion in '2-Stroke Engines' started by tony4043, Apr 18, 2015.

  1. tony4043

    tony4043 New Member

    Has spark, has gas, bike stopped all the sudden and wont start. Turns over but wont start. Checked carb, tried different carb. Clutch is fine. Checked crank seal on engine chain side but it looks good no leak. Seems to have compression. New spark plug and cap.. Can a crank seal be bad even if no leak appears? Thats all we can think of.
     

  2. dougsr.874

    dougsr.874 Active Member

    How do you know its firing......??????
     
  3. crassius

    crassius Well-Known Member

    I had a bad CDI a couple times that wouldn't spark at pedaling speed, but when cranking fast with plug out, it sparked OK - no fix except to replace it.

    Have had many CDIs that died while making a good spark, but at wrong time - search on the forum about how to make a timing mark to check that.
     
  4. bluegoatwoods

    bluegoatwoods Well-Known Member

    Also you mention a suspected bad crank seal. But I'm having a hard time seeing the connection to a simple no-start condition.

    If you could explain what makes you think this seal is preventing start-up, that might give us some more clues about your trouble.
     
  5. crassius

    crassius Well-Known Member

    oops, sorry about the timing mark thing - it is on the other forum since it has a lot of pics that won't upload here : (
     
  6. dotcom

    dotcom Member

    I just installed a new CDI and a new Magneto and spark plug but it still won't start. I checked for spark with the new electrical set up and the spark is good but still will not start. Acts like it wants to but just will not. Also cleaned the carb. Same feeling as before new electrical components installed. Any help is appreciated
     
    Last edited: Apr 25, 2015
  7. remove the drain screw from the bottom of the bowl and turn on your pepcock, you should have a constant free flow of gas(use a cup or something) check your needle setting, you may be getting too much or too little gas. also check for any vacume leaks around your intake , check to make sure your choke is engaging and disengaging too, sometimes the bolt gets lose and it floats around.
     
  8. tony4043

    tony4043 New Member

    fuel flow seems good . has spark please take a look at video and listen to the sound.


    [video]https://youtu.be/_mFSbUBYLTo[/video]
     
  9. dougsr.874

    dougsr.874 Active Member

    Be ready to ride it....then remove the plug . put about a good tablespoon of gas mix in the sparkplug hole and immediatly replace plug and try it...see if it trys to start. I once had too much oil in the gas & bike would not start
     
  10. crassius

    crassius Well-Known Member

    be sure new mag has flat side toward the case (seen a lot put in upside down)

    watched the vid & had several fresh motors take a LOT more peddling than that to get started (gets easier after break in)
     
  11. dotcom

    dotcom Member

    Motor is a few months old already and was working fine after I changed all the top end components but suddenly stopped while riding one day and wont start again. Odd thing about the new mag is there is no white wire. Only blue and black which are both soldered on, unlike the standard way Ive been screwing in the black for ground. Now it is soldered where the white one use to be soldered. But I was still getting spark with the old mag but I thought maybe it had a short so it was changed to a new one but bike still will not start. New CDI also.
     
    Last edited: Apr 26, 2015
  12. bluegoatwoods

    bluegoatwoods Well-Known Member

    Tell you what.......it just has to be something pretty simple. I'd say that it's time to use the 'search' function. Somewhere in those threads will be some kind of hint that you can use.

    You might start by having a look here.
    http://www.motoredbikes.com/google....rl=www.motoredbikes.com/&ref=&ss=472j154024j3

    That link will take you to magneto/electrical issues. It does sound, though, as though that's not your trouble. Maybe it's carburetor.

    http://www.motoredbikes.com/google....www.motoredbikes.com/&ref=&ss=6410j3781902j24
     
  13. crassius

    crassius Well-Known Member

    if all else fails, you might have to search for someone in your area that works on these
     
  14. dotcom

    dotcom Member

    by the way the problem is described, is there a possibility it is the seals or a bad seal that will cause a no start situation?
     
  15. dotcom

    dotcom Member

    A couple weeks ago, the bike was involved in an accident and the a few things bent and such and gas was leaking from the petcock so got a new one and installed it and once the new one was installed a few days , maybe a week later, the bike stopped working so I just realized I forgot to mention that I checked the new petcock to make sure the gas was flowing properly, but when the new petcock was unscrewed, the filter was no longer attached to it and is stuck somehow in the tank. We also checked the flow of gas by unscrewing the screw on bottom of bowl and the flow was not consistant. It also seems the new petcock only flows consistantly when it is positioned in the up position with the arrow facing down. Usually, it would flow normally in the up or down position and be turned off in either side to side position.
     
  16. dougsr.874

    dougsr.874 Active Member

    The brass petcocks are notorius for not flowing properly
     
  17. dotcom

    dotcom Member

    This one is not the brass kind. It is the standard chrome kind.
     
  18. crassius

    crassius Well-Known Member

    those are easily opened & fixed
     
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