Engine Trouble Engine cut out issue

Discussion in '2-Stroke Engines' started by smallengineguy, Nov 2, 2013.

  1. smallengineguy

    smallengineguy New Member

    So its my first build,
    I got this engine for 100 bucks my guess around 66cc-80cc bicycle engine (I got 2 these bad boys)also picked up
    a bike that was in rough shape one those OCC or Jesse james chopper bicycle, with no back wheel so it has one those gear bicycle rear wheel but I hooked up a chain dosnt really work well the way pedal sprockets have wide spaces between spikes so the chain falls off after few pedals so I been push starting this thing and trying my hardest get this bad boy going I been running and jumping on and holding clutch in and releasing while holding back throttle engine revs then cuts out, not spinning chain hooked up to the engine to the rear.I fooled around with the choke a few times tried different heights no such luck.

    Things I did,

    1. Drained carb bowl.
    2. Made sure I can hear my throttle needle moving up and down.
    3. Made sure wires hooked up were alright black to black and so on.
    4. Checked fuel lines.
    5. Changed manifold position so carb slants up (Didn't test yet since the adjustments)
    6. Checked and made sure my clutch wire is fine (Which is perfect but 1 issue when I turn left the lever holds clutch in)

    Do I need to pedal this thing to get engine to drive? -
    Also ordered a Alloy pull start and few odds and ends im thinking about hooking a 12v LEDs to this get its attention it needs in the night time.
    Last edited: Nov 2, 2013

  2. crassius

    crassius Well-Known Member

    you may need to get pedal power hooked up to get engine spinning fast enough to start running
  3. zippinaround

    zippinaround Active Member

  4. smallengineguy

    smallengineguy New Member

    My last attempt I hold in clutch ran down the road jumped released and gave it gas it started up but died out and I cant set idle screw quick enough keep it running? but it sounded very low when it was going when running with it.
    Last edited: Nov 2, 2013
  5. dougsr.874

    dougsr.874 Active Member

    Sounds to me like the Bad Boys got to YOU.
  6. zippinaround

    zippinaround Active Member

    screw the idle screw in a bit more so it will idle too fast when you start it, then pull the clutch and screw it out till its good.
  7. HeadSmess

    HeadSmess Well-Known Member

    remove magneto cover, cordless drill, 12....13...14mm socket on cranknut.

    strap engine down to bench. or get ya mate to hold it :)

    but wait...despite the wrong wheel, and a lousy setup that throws chains...you have had it FIRE? run? make a noise?

    its very hard to tell from your description :)

    if it fires...start by pulling the carb apart and cleaning it. cus everything else sounds fine. to a degree.
  8. smallengineguy

    smallengineguy New Member

    Ok so when I try jump starting this engine it starts but dosnt sound like a strong engine and getting a lot of power to rev it just dies out if I stop running but if I keep running bike stays started but sounds very low (Dosnt wanna rev like a strong engine) and when I instantly stop running it stops (engine) and its not trying to take off or anything either.
    Carbs fine a little rust on idle but I cleaned it up with some WD40 and sand paper toke all that rust out. (also re cleaned idle screw with a little carb clean before putting it back into carb)
  9. smallengineguy

    smallengineguy New Member

    -Drill part - Needed tool on my list, but for the time being I usually crank it with a socket kick er down but I have a alloy pull start coming in from the mail so it ties around the fly nut which is amazing and it replaces magneto box, with the same box idea with a pulley attached which is going to interfere with my pedal (its already half a inc from hitting the magneto box)
  10. zippinaround

    zippinaround Active Member

    so it does start but has no power?
  11. crassius

    crassius Well-Known Member

    if your carb has leaked fuel into the motor, it will be hard to get it to run until it is blown out a bit - excessive smoking is a sign of this

    you REALLY need to get your pedal situation sorted so you can run the engine at high speed to tell what's going on - just wasted effort without a way to keep it turning till it catches
  12. HeadSmess

    HeadSmess Well-Known Member

    cool. sanded the rust off the idle screw. yep, thats going to unblock the jet for sure :jester:

    :banghead:pULL THE CARB APART AND RUN A FINE WIRE THROUGH THE JET.:banghead::banghead::banghead::banghead::banghead:

    stop. read what is written. think. look. think. think. THINK!

    forget about pullstarts and pulleys, learn the basics. clean the carb out INTERNALLY.
  13. Sam_M

    Sam_M New Member

    i have the exact same problem.... you pedal to start it up, it sounds like its running, but when you rev it, it just dosnt have any power at all.. then as soon as youve slowed down pedaling, it just stops....
  14. smallengineguy

    smallengineguy New Member

    And it looks to be a failure on your part, I wrote down I CLEANED THE CARB, and look at my user? Small engine guy. I work more so with dirt bikes then these chines engines, I had pocket bikes and such. I toke my old carb apart today NT and also have a speedy but in process of cleaning again as parts come in idle screw was rusty because guy I bought it off had It all sitting out I did most of cleaning I just wanna know if I have to pedal and is this reason engine fails to completely start. Pull starts for I don't have to pedal more so chains just for show in case cop decides be a ***** about it and pull me over, I toke the pedal and bolt off and turned them facing out like a choppers foot rests but if I need to I can change it using a wrench for pedaling. I really suck at explaining things and spelling out parts this is why I prefer hands on work.
  15. HeadSmess

    HeadSmess Well-Known Member

    a carb, is a carb.

    have you removed the BOWL? ran a fine wire through the jet? removed jet and made sure it is clear? have you checked that the needle in the slide HAS THE E-CLIP still? and, for starters, in the middle groove? if it has dropped in the slide, it will do the same thing as a lump of dirt...block the jet. you will be able to idle, but nothing else. if you need one...solder a ring of heavy copper wire on the groove. or look on an rc car for a small e-clip.

    vice versa, if the needle is missing, it wont idle, wont rev, but will take WOT happily when up to speed.

    you stated you removed rust from the idle screw. that is an external item, that has no bearing on the carbs operation.

    the most basic part of any small engine service, and usually the first thing to do.

    there is no difference (basically) between a mikuni 24mm or an NT POS. no difference between a 427 chev or a single cylinder briggs and stratton. anything gets in the bowl, and blocks the jet, it wont RUN.

    no, you dont need to pedal to get them started. not continuously, at least. when the engines in good tune, and everythings a-ok, they should fire up and run on the first few turns. like, in less than a metre.

    just like a good chainsaw will fire first pull, or a good yx150 will fire up on the first kick.

    sorry for sounding slightly arrogant :) disparaging. sorry. i get a lot of work after a local "small engine mechanic" has declared it as unfixable... or quotes astronomical sums.
  16. smallengineguy

    smallengineguy New Member

    Buddy had a engine from like awhile ago spray painted over everything even carb can imagine how inside looked inside engine and fuel lines and so on.. magneto box completely gone (reason I bought a pull start), I bought this engine so its sitting around hooked It up and it fired but didn't run turn my back wheel when I release clutch, its not doing much but dying out cause not idle right.
  17. smallengineguy

    smallengineguy New Member

    my second engine im thinking about hooking it up to a power wheels jeep or something with a small rear atv axle and bearings to fit inside plastic with some kind a support. Im trying figure how sprocket from engine spines? Cause my clutch pad is adjusted clutch does have free wheel play when released but has a strong grip when I don't have clutch holded in.
  18. smallengineguy

    smallengineguy New Member

    So when engine starts now my problem is gear spinning but it isn't moving the bike and it just dies out? Unless I keep running with the bike.