Atomik Nitrous 140 starting problems

[my67xr]

the middle screw with the spring on it is the idle speed screw, try turning it in maybe half a turn
see if it idles then.

 

[Flynn629]

Ive tryed tightening up the idle screw and it still wont idle on its own. Im also getting quite a strong smell of petrol aswell

 

[Flynn629]

Ive like taken the idle screw out. Its there a stock setting for the idle screw? Because ive turned it a hell of alot more the harf a turn both ways

 

[my67xr]

if it doesn't idle with the speed increased,
the Pilot Jet in the carby will need to be removed and cleaned

this picture shows a carby with the fuel bowl removed from the bottom of it.
the Pilot jet is the smaller diameter brass jet, slightly above the centre Main jet

so take the carby off, you can leave the cable connected if you like.
remove the 4 screws holding the fuel bowl to the bottom of the carby, then lift the bowl off.
dry the seal/gasket that sits between the carby and fuel bowl, as they can expand when soaked in fuel, and wont seal properly when you reassemble it later.

now take the Pilot jet out, and look through the hole through the centre of it.
you should be able to see light through the hole, poke a strand of wire through it if you can (a strand from a wire brush might work)
also across the side of the jet, below the threads there might be some other small holes.
these need to be clear/see through too.

now look into the bottom of the carby where the jet screws into, at the bottom of the threads/hole, there will be a tiny hole
this needs to be open too, same thing as i mentioned above, poke some wire through it to make sure its open.
blow everything out well, compressed air is good if you have it available.

now carefully reassemble the carby, refit it to the bike and try it out

 

[my67xr]

to set the idle speed scre,
remove the air filter
look down the inlet side of the carby, you will see the slide (round cylinder)
screw the idle speed screw in until it starts to lift the slide
a rough setting height for the idle speed, is somewhere around 1.5 - 2mm up from the slide being fully closed.

 

[Flynn629]

Is the slide the real big thing that takes up most of the carby air intake if it is when im screwing the idel screw in and out its not moving, its also about 1/2cm off the bottom, thanks

 

[Flynn629]

Also the previous owner just put on a uni filter, would this have any affect? Thanks heaps guys u guys rock i really appriciate everything

 

[my67xr]

the slide is the slightly darker cylinder in the centre of the carby.
there needs to be a gap at the bottom.

screw the centre screw (w/spring) in, until the slide starts to lift
then keep turning it in until there is a gap of 2mm under the slide

 

[my67xr]

the uni filter is a bonus,
it will make your engine last longer if it's oiled, and looked after (cleaned of dirt etc, and reoiled)



if you take the idle speed screw completely out of the carby, does the slide go down then ?


if not,
the throttle cable needs to be adjusted/loosened up at the handlebars
there will be a rubber boot/sleeve on the end of the throttle cable, where it goes into the throttle.
slide it back down over the cable.
then loosen the nut that locks up the adjuster.
now turn the adjuster clockwise so it screw back into the throttle housing
watch the slide move back down as you adjust it in, at the throttle
once it stops moving down, then turn the adjuster in a touch more.
lock up the nut, then push the rubber sleeve back over the adjuster.


now refit your idle speed screw and spring back into the carby
turn it clockwise to do it up.
keep tightening it until the slide starts to lift in the bore of the carby
you need it to be about 1.5mm - 2mm off the bottom of the carbys' bore.

 

[Flynn629]

Got the carby apart what should i clean?

 

[my67xr]

is there any other parts that came out when you took the fuel bowl off ?

 

[Flynn629]

The only thing i can see which might be a slide is a skinny silver tube thing?

 

[Flynn629]

No those are all the parts that were in the carby

 

[Flynn629]

When i fully tighten up the throttle at the bars this is what it looks like

 

[my67xr]

the throttle cable adjuster needs to be loosened at the throttle on the bars.

going by your pics of the carby, there are parts missing from inside it
it is missing the Pilot jet, and float

float looks something like this-

Main jets are the ones at the top, Pilot jets at the bottom -

 

[my67xr]

here is a complete replacement carby that will suit your engine, china Mikuni 22/26mm copy
http://www.reaperbikes.co.nz/mikuni-26mm-racing-carburetor-kit-90cc-110cc-125cc/

 

[Flynn629]

Yea i dont think i had a pilot jet, it was going pretty sweet yesterday once its going? Can they still work with no piolet jet?

 

[Flynn629]

Should the pilot jet be here where the arrow is?

 

[Flynn629]

I actually just took carby off again and it looks as if its snapped off cause i can see uneven bits of gold down the hole

 

[my67xr]

yeah i guess it can run there is still the tiny hole visible in the middle of it,
if it's not blocked up, or blocked on the other side of the jet

i'm guessing someone snapped it off trying to undo it, or doing it up,
they are made of brass, so wouldn't take much

if you can, try and poke some wire through it to clear any blockages

otherwise you'll be up for a new carby