Mini Dirt Bike Problem ( HELP ME PLEASE )

[hustle]

Hi. Well my dirt bike was backfiring last time i took it out, so i cleaned the carby ect. I then started it up with the choke on and reved it fully and it didnt backfire , so i was happy. Well i took it out today. Got to the field, put choke on. Started it, It sounded like it was being reved fully when i wasn't even touching the throttle. So i tried reving it to see if it would stop it but it went louder.
I took the choke of and it just went from loud, down to off.

Now when i start it with the choke on its sound like its being reved fully.
When i start without choke, or turn choke of after starting with it on, it just getting quieter and quieter until it cuts out. I have to keep the revs up when the choke is off to keep it from cutting out.

Why is this? I have messed with the air screw on the back of the carby and nomatter where i put it it does this.

Sometimes it start ok but leave it for 10 seconds it just goes like it .

This is a video of it with the choke of. I start revving it to keep the revs up but listen as i slowly let go of the throttle..



Also heres it with the choke on ...



The air screw is 5 full turns lose from when tight. This is the same on my other bike and it runs fine ..

Could my bike need a new air filter.

I have just cleaned out the carby.

 

[hustle]

Just found the manual for my bike. This looks like it comes with every pitbike loncin make.

Acording to this manual, my bike has a battery and electric start lol.....

 

[hustle]

Latest news .. Tried kicking bike over.

Didn't start. Didn't even nearly start.

Checked spark plug, thats fine. emptyed fuel out of carb with the screw at bottom.

Tried kicking it with choke on and off for 10 minutes. Not a chance. All that happened was, i had to keep undoing the screw on the carb to let the petrol in the carb out because i kept flooding it.
Tried bumping it. Didn't wanna know.

WHAT WRONGE?????????

 

[user 2364]

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[hustle]

Now irnow i wont start. Maybe i flooded it where i kept trying to kick it over. Or maybe i have the air and fuel mixture screw to much on one. I havnt cjanged this thoe so it should be fine. Ill try starting it in a few hours and update you.

 

[No-Fear]

if it doesnt spark, i'd be checking electrics to see if u are gettin spark anywhere.

 

[mjc85]

Yeh check the spark, if no spark then follow these steps.

1. Check all the wires to make sure they are all joined and not shorting the circuits somewhere.

2. If wires check out next cheapest thing to do is change to another spark plug

3. Change coil

4. Change CDI

5. Change stator (real pain in the ass, best to get the bike shop to do this and will prob cost you $100-200 for parts and labour).

 

[No-Fear]

LoL mcj85, what is oil going to do to help the engine spark? lmao, thats made my day!!

 

[mjc85]

LoL mcj85, what is oil going to do to help the engine spark? lmao, thats made my day!!

What you talking about ?

 

[No-Fear]

LMFAO! never mind, i read ur post to quick, didnt see the 'c' before oil

 

[hustle]

It is getting a spark. I tried different spark plugs. They all spark so its nothing to do with that.

 

[mjc85]

Is your throttle working ok ? The slide isn't stuck open in the carby ? Your air filter isn't clogged with crap? And your carby is flowing properly ?

 

[hustle]

I tried starting it this morning. I just kicked it over constantly and it started once with the choke on.

It was revving full, so i put the air screw lower so it was normal.
As soon as i reved it with the throttle, it didnt rev, just slowly cut out.

I took the carby off. Didn't know what to do with it so i just blew it incase there was any air. I put a new air filter on it.

Put it back on. Tried kicking it. All what happened was i had to undo the carby screw to let the petrol out coz it got flooded. It wouldn't start. WHATS WRONGE?? p.s its deffinatelly getting a spark.

How do i check if petrols getting to the engine. . and could there be water in my petrol ?

 

[mjc85]

Pull your carby apart and clean it out prob shit jammed in somewhere.

 

[hustle]

i put the spark plug in that i got with the bike when i first bought it .. put it on real tight.. added a little more oil.. put the old air filter back on ..

VICTORY IS MINE !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! THANKS GUYS .

 

[No-Fear]

sounds like it's ideling a little low, turn the idle screw up a bit mate.

 

[hustle]

i turnt it down the lowest it will go without it cutting out. So its to low?
The reason i turnt it down the lowest it will go without cutting out is because when i put the choke on, it sounds like the engine is being revved full. Is it meant to rev this high with the choke on?

 

[No-Fear]

it's meant to rev a little high when choke is on, but you only have choke on for a MAX of 15-20seconds, then just let it idle and when it soudns like it will die, just give it a little rev.

 

[Dabomb]

yes yes....ur bike is cold if you start it the first time....choke dumps more fuel so it warms up quiker....that makes the bike rev a little higher.....When the bike is cold and you rev it the air filter will make a noise and revs will decline...
just let the bike WARM UP!

 

[hustle]

Update.
The bike is not fine . Its been ok all day yesterday and today but i started it with choke on for 15 seconds then turnt it off and the engine stayed on but the air screw was to low so i turnt it up. It stayed on fine. Then cut out. Then it done exactly wat it was doing A few days ago. Wouldn't start.
Im not shore whats wronge now because it was fine.

*YAWN* Tired of this now. Anyone help me?


EDIT: I HAVE FOUND THE FULL PROBLEM TO WHY THE BIKE HAS BEEN DOING THIS FROM THE START NOW.

I allways have my bike on reserve. No matter if theres alot or little fuel in it.

I have filled the tank up. Took the petrol tube out and put petrol to reserve. No fuel comming out at all.

Put the petrol to on and theres fuel.. yay........


Now how do i unblock the fuel reserve tap? is it to do with the petrol tank or the carb?