Wont start. Has a new carb and pipe.

Discussion in 'Motorized Bicycle Trouble Shooting' started by lucajo16, May 15, 2017.

  1. lucajo16

    lucajo16 Member

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    The other day my bike wouldnt start. I had just finished installing an expansion chamber and a new high performence exhaust. I checked for spark before locking it up and its sparking. Has a new ngk spark plug but it wont fire. Could it be the jetting? The carb is a dallato clone.
     
  2. Potato_In_Exhaust

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    Probably too much fuel making your plug wet causing the no spark issue.
     
  3. crassius

    crassius Well-Known Member

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    first, I'd try the old carb again
     
  4. lucajo16

    lucajo16 Member

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    Well there is a problem. I threw out the old carb. I took carb cleaner to it and it wouldnt start. With the new carb itll start but its an uphill fight. But i have pulled out the spark plug and its soaking wet with fuel. If its getting to much fuel i assume it needs to be re jetted.
     
  5. crassius

    crassius Well-Known Member

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    sounds more like a problem elsewhere if neither carb gets good starting
     
  6. lucajo16

    lucajo16 Member

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    Well im not a master bike builder i have about 6 bikes under my belt. Let me ask this. I get spark, fuel (( i think)) air and compression what could it be? Could it be that the timing on the electrical could be off? Does this sometimes happen with these engines? Ive had this happen where the mag went out but i guess i will tear it down slowly over the next few weeks. I think its jetting to me because a few times it would start but then stop right away. I did get it to start with a different pipe but again its an up hill battle.
     
  7. bairdco

    bairdco a guy who makes cool bikes

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    Jetting wouldn't make it not start, unless it's waaay off, like you're trying to run a 40mm carb or something.

    Go back to basics. You have spark, so you need fuel and air. If your plug is wet, you have fuel, but maybe your mixture is too rich? Do you have fresh fuel?

    Is there an air leak anywhere? When you swapped the carb and pipe, did you make new gaskets? Did you mess with your magneto and put the magnet in backwards?

    Is your kill switch grounding out?

    Choke working? Throttle opening?

    Take one step at a time.
     
  8. lucajo16

    lucajo16 Member

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    Wellhttps://m.facebook.com/story.php?story_fbid=1089501044488501&id=100002858486481

    Well this is what the spark plug looked like last night. What do you mean by mixture? If its gas to oil its 4oz to a gallon. If its jetting i havent adjusted that yet. Its the stock one that came with the high performence carb. I may take off the old tubing and put a new one without a filter to see if its the filter not giving the carb gas.
     
  9. Potato_In_Exhaust

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    Yes, try to run it without the air filter foam. My bike won't start with the foam filter in it but once I ditch it, it starts right up and runs fine. But then that all starts with the wrong jetting though, I think, but still if running without the foam filter works then it works! Been running fine without filter for many miles now too, no problem.
     
  10. lucajo16

    lucajo16 Member

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    Well i dont know if the clone dalloto has a foam filter but when i have time ill take off the filter and try again. Also my oil to gas mix is 4oz to 1 gallon. I will buy another stock carb and pipe and see if the problem persists.
     
  11. crassius

    crassius Well-Known Member

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    doubt the pipe makes much difference as long as it's not clogged - I loosen pipes 1/8 inch or so to test

    could be carb, but sounds a bit like a weak CDI
     
  12. Tony01

    Tony01 Member

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    Plug is fouled, try a new plug gapped to about .031. Lean it up a bit I think too
     
  13. Amarion1

    Amarion1 Member

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    I was just thinking the same. But maybe could try cleaning the plug and checking gap. May not be gapped enough
     
  14. Tyler6357

    Tyler6357 Member

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    Don't forget to check for leaks, at the carb/intake connection and at the intake/intake manifold connection. Make sure you are getting fuel, is the spark plug wet?
     

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