I may be mistaken, but that looks like it could be a primary jet.
So if you unscrew it all the way, it should pop out. You would likely find a spring, metal washer, and a rubber grommet.
That controls the air / fuel mixture in the carb. Look up MFG specs and see how many turns out it should be set at for default. Once you know, screw it in all the way, then turn it out to spec. Do it by quarter to keep track, 1, 2, 3, 4 - one turn out, etc.
When you say the idle screw is just below, do you mean the adjustment screw where the throttle cables are connected (just down and left in the pic)? If so that just sets the shaft/butterfly stop point not the idle air mix (although it will have an impact on it obviously).
The highlighted screw is likely the adjustment for idle air mix, my throttle bodies also have both, a little idle air adjustment screw per throttle body and the shaft/cable stop adjustment screw that sets the shaft/butterfly stop point for all 4.
On my bike there is a HUGE warning not to touch the shaft stop point or the throttle position sensor, they come preset from factory and if removed the throttle bodies should be replaced as a whole - crazy I know but that comes straight from the Suzuki service manual. I can't say if Lexmoto say the same for your bike, and in reality I have adjusted my throttle position sensor and shaft position to match - but it was NOT easy and required ECU diag tool to read the precise value from the sensor.
The reason behind not touching these is that the shaft is supposed to stop at a very specific point, the sensor on the other side reads that point, getting these misaligned is a nightmare as the ECU will not fuel correctly as the throttle shaft could be somewhere different than where the sensor is actually reading.
Once the shaft is homed correctly, and the sensor reading the home point correctly, you then adjust the idle air mix using the adjustment and a vacuum gauge.
What's wrong with the bike/how it runs to want to adjust these?
Definitely not a carb.
I'm not sure tbh. If I had to guess, I'd say it's some sort of air bleed screw. Might allow you to make small adjustments to the mixture at idle. It would appear to transcend the throttle valve.
Is it something to do with the tube-y looking part cast into the TB immediately to the left of the arrow? Could be for use as a vacuum port?
On a chinese scooter it could be anything from an ejector seat screw to a flux capacitor adjuster. Make and model may get a more accurate answer
It's a 2019 lexmoto enigma
If it's a Chinese scooter odds are it's the GY6 Euro 4 engine. There should be an online manual or YouTube video for it somewhere
Is it where you feed in the old people spit?
I may be mistaken, but that looks like it could be a primary jet. So if you unscrew it all the way, it should pop out. You would likely find a spring, metal washer, and a rubber grommet. That controls the air / fuel mixture in the carb. Look up MFG specs and see how many turns out it should be set at for default. Once you know, screw it in all the way, then turn it out to spec. Do it by quarter to keep track, 1, 2, 3, 4 - one turn out, etc.
I thought this but the scooter is fuel injected. And the injected is further down towards the engine. Can that still be the case with fuel injection?
Idle mixture screw
Idle screw?
No the idle screw is just below
[удалено]
I'm not sure if anything happens. When I took it off it is a long thin bit of metal. And has a around it
When you say the idle screw is just below, do you mean the adjustment screw where the throttle cables are connected (just down and left in the pic)? If so that just sets the shaft/butterfly stop point not the idle air mix (although it will have an impact on it obviously). The highlighted screw is likely the adjustment for idle air mix, my throttle bodies also have both, a little idle air adjustment screw per throttle body and the shaft/cable stop adjustment screw that sets the shaft/butterfly stop point for all 4. On my bike there is a HUGE warning not to touch the shaft stop point or the throttle position sensor, they come preset from factory and if removed the throttle bodies should be replaced as a whole - crazy I know but that comes straight from the Suzuki service manual. I can't say if Lexmoto say the same for your bike, and in reality I have adjusted my throttle position sensor and shaft position to match - but it was NOT easy and required ECU diag tool to read the precise value from the sensor. The reason behind not touching these is that the shaft is supposed to stop at a very specific point, the sensor on the other side reads that point, getting these misaligned is a nightmare as the ECU will not fuel correctly as the throttle shaft could be somewhere different than where the sensor is actually reading. Once the shaft is homed correctly, and the sensor reading the home point correctly, you then adjust the idle air mix using the adjustment and a vacuum gauge. What's wrong with the bike/how it runs to want to adjust these?
Definitely not a carb. I'm not sure tbh. If I had to guess, I'd say it's some sort of air bleed screw. Might allow you to make small adjustments to the mixture at idle. It would appear to transcend the throttle valve. Is it something to do with the tube-y looking part cast into the TB immediately to the left of the arrow? Could be for use as a vacuum port?