Keeway k light 125 - low rpm popping and hesitation

[SPORADIC]

Hi all

Trying to get to the bottom of fixing this bike for my partner. Picked it up a while back and been doing little bits to it here and there.

The bike has done just over 3k miles on a 2019 reg.

The issue:

Giving the throttle a little blip or even a slow rev, it hesitates, pops, splutters etc then revs fine over 3k. if you rev it higher up the range then blip throttle, it will likley rev ok. It idles fine and only really cuts out after blipping or slow revving.

What iv fixed so far -

The 5v rail/supply to the map/intake sensor had low voltage/resistance. Traced this back to terminals needing tighening up as they corroded. Replaced the sensor while i was there. I deal in electronics so im not too bad with a multimeter. I have gone over the wiring diagram and checked i have the correct voltages/resistances etc to as many things i could test. Battery, rectifier etc all working well.

I have replaced the sparkplug for a fresh new ngk as i read the factory fitted are pants.

I have noticed a couple of things, i do feel like it smells a bit too strong of fuel. if i squeeze/restrict the intake manifold to restrict the airflow it clears up the throttle response right away and doesnt pop or lag.

There's a lot of induction noise, kinda like a bogging sound through the intake when revving.

Next step i think is valve clearance's

Just looking for a bit of direction. Thanks all