So your HT bicycle engine won't start, well let's take a look

Discussion in 'Motorized Bicycle Trouble Shooting' started by Al.Fisherman, Nov 9, 2011.

  1. sboricic123

    sboricic123 Member

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    Re: So your HT won't start, well let's take a look

    UPDATE: I think I might be getting somewhere. About a week before I started having these dang problems, I took of the muffler and cleaned it out. Well, I guess I may not have gotten everything. So, I took off the muffler again this morning and ran it without it. It seemed to run great. Damn loud though. LOL! I have it soaking in heavy duty oven cleaner right now and will try it again later with the muffler back on to see if that was part of the issue. If the oven cleaner doesn't work then I'll try another guys trick, I forget who posted it, let it soak in gas overnight, drain it the next morning, then set it on fire. Will keep you updated.
     
  2. sboricic123

    sboricic123 Member

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    Re: So your HT won't start, well let's take a look

    Okay it's all back together and running the way a bike engine should run. I guess it was just a clogged muffler causing it not to run properly. I used oven cleaner, gasoline and a propane torch to loosen up any debree that way blocking it. Then air hosed it out.

    Check muffler for clogs may as well be added to the list to check.
     
  3. Jesse_James

    Jesse_James New Member

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    Re: So your HT won't start, well let's take a look

    I can pedal the bike (very easily) with the clutch engaged. This shouldn't be and this is also a reason I can't start my bike. How can this be resolved?
     
  4. Al.Fisherman

    Al.Fisherman New Member

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    Re: So your HT won't start, well let's take a look

    Check cables to make sure that it isn't too tight, then adjust the clutch. Remove the lock screw, adjust flower nut (back off the nut), then replace screw when finished.
     
  5. nipdatrip

    nipdatrip New Member

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    Re: So your HT won't start, well let's take a look

    Having a carburetor issue getting fuel uo the jet but the fuel is not going into the pisteon getting spark and everything not surfe bike has never started just put it together yesterday need help please
     
  6. GearNut

    GearNut New Member

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    Re: So your HT won't start, well let's take a look

    Which kit do you have?
    Which carburetor did your kit come with?
    Have you started on the checklist that Al.Fisherman has on post #1 of this thread?
     
  7. bmw2002

    bmw2002 New Member

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    Re: So your HT won't start, well let's take a look

    hi all i have proper spark compressiion no leaks at the head or base gasket and fuel! bike still will not start any ideas? would a clogged muffeler really keep it from starting?
     
  8. GearNut

    GearNut New Member

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    Re: So your HT won't start, well let's take a look

    Yes, if the muffler is severely clogged the engine will not start.
    Try removing it and then starting it.
    Note: do not ride it without the muffler or at least a head pipe installed. Engine damage can/ will occur if you do.

    Another thought: if the engine has become severely flooded it will not start either.
    Just letting it sit for a few minutes will not clear it (like a 4 stroke will) as the excessive fuel will simply puddle up on the bottom of the sealed crank case cavity. It can take weeks for that to finally evaporate.
    Removing the intake manifold, placing the piston at the top of it's stroke and blowing out the cases with compressed air for a couple of minutes will clear such a flooded condition.
    Be very careful as the escaping fumes will be VERY flammable.
    No cigarettes anywhere near the area!

    Another less invasive way to do the same thing is to remove the spark plug and place the piston at the bottom of it's stroke. Slip about a foot of aquarium air hose over the tip of a blow gun. Using a flashlight and patience guide the hose down into one of the transfer ports and blow out the cases for a few minutes. All the air and fumes will escape up and out of the spark plug hole.

    If no compressed air is available...
    Disconnect the ignition wires.
    Remove the spark plug.
    Drain the carb of fuel.
    While holding the throttle wide open, pedal around for a couple of minutes like you are trying to start the engine. Get as much air flowing through the cases as you can.
     
    #48 GearNut, Feb 16, 2014
    Last edited: Feb 16, 2014
  9. bmw2002

    bmw2002 New Member

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    Re: So your HT won't start, well let's take a look

    thank you so much but i just tried even pullling it with the car and removed themuffelerandabsolutly nothing!!! i pulled it around for about ten minuites...i am so stumped... as i said no blown base nor head gasket... i have no clue where to go from here!!!!
     
  10. 2door

    2door Moderator
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    Re: So your HT won't start, well let's take a look

    Sir you already have a thread going in the troubleshooting section, http://motorbicycling.com/showthread.php?t=53634 regarding this problem. Please restrict your questions to one area/thread and not in multiple locations.
    Thank you

    Tom
     
  11. bmw2002

    bmw2002 New Member

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    Re: So your HT won't start, well let's take a look

    i am new to this site and didnt thinkit would matter i need all of the help ican get at this point i thought that was the point of this site,one biker helping another!!! thanks for your additive!!!
     
  12. John E

    John E New Member

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    Your Engine Won't Start? Replace the cheap factory plug with an NGK B6HS. Do it NOW!

    I spent three hours trying to get my just-completed Chinese 2-stroke bike to start. :-||
    It had fuel and compression. The spark was very weak, but there was a spark. All I could get it to do was to "pop" every now and then with furious pedaling.

    Out of desperation I read through some posts and went out and bought an NGK B6HS plug at my local O'Reilly's Auto Parts store.

    I installed the new plug, cranked the bike down the driveway and it started up and ran perfectly.

    LESSON LEARNED. THROW AWAY THE FACTORY SPARK PLUG AND BUY AN NGK B6HS.

    If the B6HS runs too cold (carbon deposits or dark electrode insulator) use a slightly hotter NGK B5HS instead.
    If the B6HS runs too hot (electrode insulator is white, not tan, after hard running) use a slightly colder NGK B7HS plug.

    Use which ever plug gives you a light tan colored electrode insulator when run hard.
     
  13. Davezilla

    Davezilla New Member

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    Yup... a good plug and gapped properly makes all the difference...
    These engines like a tight gap like .024 to .026" ... if it's hard to start or becomes hard to start, closing the gap a little usually helps.
     
  14. jgd1127

    jgd1127 New Member

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    I have a brand new motor got it all hooked up have fuel in carb have an alright spark I guess the best I would get and I have great compression I can push it up my driveway and ride it down popping the clutch pulling throttle and it will not start what so ever I just went and bought and ngk b6hs spark plug and still nothing I don't know if I'm not getting enough fuel in the cylinder or not the plug smells like fuel but I not wet when I pull it out so is that my problem and how do I fix it if so the carb seems to be getting fuel please help
     
  15. 2door

    2door Moderator
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    Did you follow the troubleshooting guide I posted for you in your other thread?
    What did you find when you went through the steps to determine what was right/wrong?

    Tom
     
  16. jgd1127

    jgd1127 New Member

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    Well I went through checked for spark I had a weaker spark so I changed the plug with an ngk b6hs spark plug and the spark is better I pulled the drain screw on carb bowl plenty of fuel flowed out and has plenty of compression it has resistance when I push it engine brakes when I release clutch I pulled the spark plug it smell like fuel but is not wet idk I it should be wet or not the cylinder smells like fuel I checked the timing that looked ok I checked cdi I got a reading of 40 to 50 on black and blue wire and around same on spark plug wire to blue wire so idk if the cdi is bad but it wouldnt have a spark would it so I really dont know what else to check
     
  17. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    Did you read my post in your thread?
    Do it, do it now.
     
  18. Zsm0115

    Zsm0115 New Member

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    Dumpster find won't run

    Hello all. I pulled a 80cc 26" mountain bike out of my apartments dumpster. i have no idea what happened to it but i tried to get it running. I got new spark plug, drained tank, new fuel mix, new fuel filter and line, checked all the wiring and nothing. so i tore down the whole kit and everything looks fine. re-assembled the whole thing and got 2 or 3 pops out of it (after riding around for 15 minutes) and nothing since. cylinder moves freely, has compression, getting fuel, spark is very weak ( light purple to white). i tested the CDI and got really weird ranges. i cant test Magneto since i have a the 2 wire model ( black wire is soldered to coil and to frame). i don't want to dump a bunch into it. any help will be great. :-||
     
  19. MEASURE TWICE

    MEASURE TWICE Active Member

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    I'm mostly know Briggs engine, but still similarly a work woodruff key or other parts on the two stroke engines that the magnet and coil if are slight worn offset timing and you may have that symptom. See the beginning of this thread and also others would probably chime in. Note under compression spark needs more voltage. There are spark testers that I never invested in. But I see them for under 10 bucks at auto supply shops.
     
  20. crassius

    crassius Active Member

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    you need to read the steps in the motor won't start list

    meters can't test CDIs, but can test mags of any type

    both are probably good though if you have spark
     

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