Bike starts but wont run.. fairly complicated .. read on

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battler

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Ok, i have a stock pitpro 125 cc with a lifan engine., been very happy with it, lots of grunt, no breakages of anything, BUT..

Now i have boggled over this for a few days checked what i know which is little and i still have no idea.

So this is the situation:

Got home from a big ride, hosed down carfully and wiped clean. Put away, pulled it out a few days later tryed to start it. Struggled a bit to start but got it with the choke on, ran the choke for a bit which was fine but when i let it off the engine normally stays running but kind of chokes along, sometimes cuts out. Especially when i put it into gear it struggles more and when i go to move off in first it splurts chokes and cuts out on the spot. (not a happy bike i conluded)

Checked fuel got plenty, checked to make sure fuel flow is open, checked motor cut switch, checked oil, all seems fine but wont run off choke.. Now i leave this question open to anyone why wont it run?

My guess was a gear box allignment issue but i really know little apart from the general areas. So all and any suggestions would be appreciated.

Thanks:)

EDIT: After reading up on a cleaning thread which i should have done earlier i didnt put a bag over the air intake even though it is well covered up so water may have got in to the carburetor (<spelt wrong i know) Not sure what this may do but its a hint.
 
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if that happend to me..

1. drop all fuel and replace with fresh *incase of water infuel
2. take carbie off and clean
3. pop plug out while carbie is off and kick it over a few dozen times just incase water is in block or head.
4. check there isn't any water in any of the power cables, spark plug etc.

try that and see how you go .
 
clean carb
new fiel(98 octane)
new plug
new oil

as pete said take plug out and kick over say 10 times to clean the **** out abit...

also clean tank and clean the in tank fuel filter while your there
 
My guess is much like the other guys who posted already: You stored your bike with some water in the carb float bowl. Water gets in there either via running down the throttle cable, or leaking in the joint with the throttle cable and slide cap (always happens to my OKO26), or it runs in the carb intake after getting thru/past your air filter. So next time you started it, it sucked water up the jets, ran as rough as, plus you probably fouled your spark plug. After storing, you might have also let some moisture into your engine's top end which has rusted your bore or rings just a little.

As no_crf wrote, you might have got water into your electrics. But I pressure wash all the time and never have a water issue with 2 china bikes and electrics.

Now: Take the whole bowl off and clean it out. Put a new spark plug in. Start her up. Run it until fully warm and then store it.

Next time: Remove air filter before washing. Put a plastic bag over the carb intake using a rubber band to hold it on. Wash bike. Remove plastic bag. Turn fuel flow off. Remove carb float drain screw and drain the fuel + any water out. Spray Inox or WD40 on your carb slide while the air filter is off. Reinstall bowl drain plug and turn fuel back on. Start your engine and run it for a few minutes to lube the insides of your engine, and dry out your exhaust.

btw: I tried using sikaflex to seal the throttle cable to slide cap junction but it only seals good until the next time I move the cable or carb for any reason.
 
Yep , sounds like water in the float bowl ....... It can cause all sorts of weird problems ..... sometimes the engine can start easily , idle and run great at low revs but splutter , crackle , pop or bog as soon as you hit the throttle ...... and it can do that with only a small amount of water in the bowl .......

What happens is that since water is heavier than fuel it sits right at the bottom below the main jet ...... if you apply the throttle gently , fuel can be pulled up the jet without lifting the water ...... but as the engine revs and the suction increases ....... up goes the water into the emulsion tube where it "gurgles" around to cause intermittent fuel flow without being pulled into the engine ..... when you back off , the water drops back out into the bowl ..... LOL ... It had me stumped at one point many moons ago until I wisened up to it ..... Sometimes you can get it out by draining the float bowl via the drain screw ...... but in some carbs (genuine Keihin) enough stays in there to cause crackling and missing at higher revs ... IF you wet the filter during a ride or hose down ...... it can hang onto the water right up until you next start the bike ..... a wet filter also causes sputtering when you try to rev the motor .........

Hey numroe , have you tried putting a piece of tight fitting rubber fuel hose over the throttle cable and cable nipple (like a sleeve) to seal them ???? If water can get in ... then the top of the carb would also be sucking air ...... a hidden cause of bogging when you try to run lean jetting since it bypasses the slide and reduces suction on the needle jet and main jet ....... It could also cause hard starting .........
 
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Hey numroe , have you tried putting a piece of tight fitting rubber fuel hose over the throttle cable and cable nipple (like a sleeve) to seal them ???? If water can get in ... then the top of the carb would also be sucking air ...... a hidden cause of bogging when you try to run lean jetting since it bypasses the slide and reduces suction on the needle jet and main jet ....... It could also cause hard starting .........
No, not tried that. I'll look into it though. I've rubber weld taped the join between the cable and the pivoting metal thing in the slide cap. So I assume the water (and as you say, air) might be getting in via the join between the metal fitting and the slide cap alum casting.

I tried sikaflex sealing that join, but as mentioned the seal gets broken easy via handling or vibration.

Come think of it, I could just epoxy arildite that join since my cable angle to the carb need not change.
 
Thanks for all the great advice from everyone.

Im very new to the whole thing so i have a feeling its going to take a while to figure it all out but ill get there.:rolleyes:

Thanks again
 

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