I have clean the carburetor but nothing helps
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When you cleaned the carburetor, did you take all the jets out and blow air through them and all the passages?
If not, you might have blocked jets or passages.
Yamaha makes a carburetor cleaner for motorcycle carburetors, it is very expensive, but if you can get it I would recomend that you fill your carburetor with it and let it soak overnight, then drain it the next day, and blow air through all the jets and passages.
I have had excelent results using this cleaner. It removes all the fuel varnish and deposits, without damaging rubber or plastic parts. It is the next best thing to muriatic acid (which will destroy rubber parts)
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'88 Corolla, AE92 SR-5, 7A-FE swap/GT-S suspension
'87 Corolla, AE82 FX-16, 4A-GZE swap (autocrosser)
'03 Tundra 4X4 Access Cab, (FX tow vehicle/Home Depot runner)

Modification: Changing something to what you thought it should have been from the start!