gs/gx/en 125 carb problems?

[pictish]

Not really an overland related question but thought i might ask.

My little 125 seams to be very ill. Its a gx125 2003 model.
Its sitting at 8000 revs throttle fully open [ not screaming] but when changing up a gear you lose all power. This is happening from 3rd to 4th gear lower gears it screams with the throttle open and changes up fine before 8000 revs.
I have also noticed a pulling/jerking motion when the throttle is held in position[ like its trying to speed up] even on the straights. the throttle isnt always fully open when this happens.
It also cuts out alot when stopping.
When you use the choke to start nothing happens[ starts then dies] until you blip the throttle then it sticks at 6000 revs.
Its also very slow even considering im a reasonable large chap[ about 15stone] and totally dies on hills.
This is not what happened when I rode a honda 125 so was wondering if its a bike problem or do I just need to lose some weight.

Spoke to a guy at work he thinks carbs needs cleaned or its suffering from fuel starvation.

[Joe C90]

Sounds about right, strip and clean the carb. don't use anything made of steel to clean the jets out with. A can of carb cleaner and a new toothbrush will do the trick.