50cc 4 stroke cuts out after few seconds

[Guest]

hi, i need help with i problem i have been having for the past few hours

i bought the bike yesterday and rode it back from Chatham to Dartford, it ran fine all the way back, today it was running for a few hours, just round town. it was sitting for a few hours and now it is having problems starting on kick start and electric start. it will tick over for a few second, 20 at the most. when i try to rev it will cut out straight away, it way be because its cold but it started fine this morning. i would really appreciate any help i can get, as this is my first bike and dont really know what to do, thanks alot.

[Susieque]

Don't know anything about your particular bike but I'm assuming it has a choke and you're using it when you first start the bike from cold?

You may find that you need to let it run for a while on the choke without touching the throttle. This is the case on my bike.

[Guest]

Don't know anything about your particular bike but I'm assuming it has a choke and you're using it when you first start the bike from cold?

You may find that you need to let it run for a while on the choke without touching the throttle. This is the case on my bike.

it doesnt have a choke that you can turn off, it has automatic choke, but when i start it, it cuts out without me touching the throttle. and will only tick over for a few seconds

thanks

[mealexme]

simple things - has it got petrol?

As I say in many of my posts, I have no mechanical knowledge but sounds like something may be blocked, ie fuel lines/filter. Do you know if the bike has been run so long that there was no petrol left in the tank? As that could suck crap into the lines (supposedly)

[Guest]

simple things - has it got petrol?

As I say in many of my posts, I have no mechanical knowledge but sounds like something may be blocked, ie fuel lines/filter. Do you know if the bike has been run so long that there was no petrol left in the tank? As that could suck crap into the lines (supposedly)

hi, there is petrol in the tank, i will check fuel filter and lines to see if there is a blockage, thanks for your advice

[eastanglianbiker]

how much petrol is in the tank as most bikes have a small amont left in them when they run out,has it got a reserve position on fuel tap havet you treid putting it on reserve if it has fuel tap?

[Tango]

Tank breather may be blocked....try running it with the filler cap open to see if this helps.....

[Guest]

Tank breather may be blocked....try running it with the filler cap open to see if this helps.....

Hi, still nothing, I tried disconnecting the fuel filter and seeing if fuel came through bit it didn't, so u took it off and gave it a blow through and tried but still not starting. Thanks alot for the suggestion, does anyone have a step by step guide of how to remove the carb, my make is a direct bike db50qt-11 would appreciate any links that tou can supply.

[Fozzie]

If fuel wasnt coming out then your fuel tank needs switching to reserve

Flick it and wait a minute then try. If it started and now doesnt at all it sounds like it was running dry. I'd fill the tank a bit as a precaution to check. If not you can always siphon it back out.

[mealexme]

If fuel wasnt coming out then your fuel tank needs switching to reserve

Flick it and wait a minute then try. If it started and now doesnt at all it sounds like it was running dry. I'd fill the tank a bit as a precaution to check. If not you can always siphon it back out.

I dont think 50cc's have a petcock do they?

As for guides, it should tell you in the haynes manual, and if you plan on having the bike for a number of years it is worth buying one

[Tango]

Is this bike likely to be Fuel Injected? If so it could be the fuel pump.

[Bonniebird]

From the manual page 25:

Checking the carburettor

In the unlikely event that your scooter fails to start please check the air pilot screw on the side of the carburettor. It should be 2.5 turns out. Screw all the way in and count the

number of turns out.

There's an illustration too.

http://www.scooter.co.uk/manuals/Manual-DB50QT-11.pdf

[mealexme]

From the manual page 25:

Checking the carburettor

In the unlikely event that your scooter fails to start please check the air pilot screw on the side of the carburettor. It should be 2.5 turns out. Screw all the way in and count the

number of turns out.

There's an illustration too.

http://www.scooter.co.uk/manuals/Manual-DB50QT-11.pdf

Good find Bonniebird!

[Guest]

From the manual page 25:

Checking the carburettor

In the unlikely event that your scooter fails to start please check the air pilot screw on the side of the carburettor. It should be 2.5 turns out. Screw all the way in and count the

number of turns out.

There's an illustration too.

http://www.scooter.co.uk/manuals/Manual-DB50QT-11.pdf

hi, ive tried this but still nothing, does anyone think that there may be a blockage inside the carb, thats all i can think of

[Bonniebird]

Could be. There's a general Haynes repair manual for Chinese/Taiwanese scooters etc but I can't see a specific one for this model. If you are going to take it apart i would suggest you be methodical in what you do and take photos as you go along to make sure you get it back together OK

[Guest]

Could be. There's a general Haynes repair manual for Chinese/Taiwanese scooters etc but I can't see a specific one for this model. If you are going to take it apart i would suggest you be methodical in what you do and take photos as you go along to make sure you get it back together OK

yer, i was going to get the haynes chineese scooter manual but dont have the money, cos ive just spent it all on the scooter, lol. thanks alot for everyones help sofar, i really appreciate it!

[Bonniebird]

Were you sold this bike as a runner because it shouldn't break down within a day of getting home!!

[Bonniebird]

See if you can download a manual

http://www.filestube.com/c/chinese+scoo ... nes+manual

[mealexme]

Have you tried starting it since? Maybe you flooded it the first time or something. Although that should sort itself out once it is on, but it may be worth a try.

Have you checked the spark plug? Has it got a weak spark?

I have a scooter Haynes infront of me (not a chinese one, but it may help)

It says

Stalls After Starting

Faulty automatic choke. Check connections and movement

Ignition malfunction

Carb malfunction

Fuel contaminated

Inlet air leak. Check for loose carb-to-inlet manifold connection, loose carb top

Engine idle speed incorrect. Turn idle adjusting screw until the engine idles at the specified rpm

That last one may be hard without a rev counter

If you are anything like me you will have no idea what any of this means, but if anyone thinks that any of those are likely, then I will do my best to copy out the haynes (unfortunately I cant scan it) or put a step by step guide of how to do the most likely cases

[Guest]

ok so a bit of an update, i took the carburettor off, gave it a clean and put it back on. started but cut out soon after. checked all my fuel lines, all fine. reset my valves. still nothing really running out of hope now. really would appreciate help.

[Tango]

You've got oil in it?

Is the fuel tap operated by vacuum from the manifold? Does it have a "Prime" position? If so, switch it to that and try again....but only for a short while as you could flood the carb.

Is the plug OK? What colour is it? Should be a light brown colour......white = Too lean...too much air/not enough fuel.......Black = Too rich.....not enough air/too much fuel.

Check for any loose connections around the bike......battery terminals, earth connections etc.

Does it have a cutout switch on the stand? could this be faulty causing the bike to cut out?

I saw that there is a helpline number on the thing that BonnieBird posted.....maybe give that a call to see if they can give you some ideas.

Unfortunately diagnosing problems over a forum can sometimes be difficult.....so all we can do is give you some hints on what could possibly be the cause.....

Good Luck

[Guest]

I've just put in a new spark plug, and I've just noticed that the fuel gauge isn't working, could the problems be related?

[eastanglianbiker]

fill it up with petrol

[Harrydh3]

im dumbfounded mate sounds like youve tried everything, though mine did this when it had drank all the oil (have you checked the dipstick?) haha confuzed the hell outa me for an hour lol