Carburetor size?

[handyman]

  I want to buy another carburetor for my 49cc GY6139 Tao Tao scooter, With a 100 BBK in it.  I purchase a 24MM carburetor and cannot seem to make it work, I ordered a variety of jets and the smallest one is a 100 and its just to big, and my stock one is an 18mm, so I guess it would be a 20mm.  I just wanted to ask and make sure that size would be correct, I know its a trial and error.  Anyone needing a 24mm carburetor can have it for $20.00 I will list it in the for sale section.  Also when my scooter is warmed up for a while, The idle goes UP and DOWN, up & down, up & down, does anyone have any suggestions, maybe the choke assembly or inricher? 

[KSR Moto]

Jun 23, 2018 6:34:41 GMT -5 handyman said:

  I want to buy another carburetor for my 49cc GY6139 Tao Tao scooter, With a 100 BBK in it.  I purchase a 24MM carburetor and cannot seem to make it work, I ordered a variety of jets and the smallest one is a 100 and its just to big, and my stock one is an 18mm, so I guess it would be a 20mm.  I just wanted to ask and make sure that size would be correct, I know its a trial and error.  Anyone needing a 24mm carburetor can have it for $20.00 I will list it in the for sale section.  Also when my scooter is warmed up for a while, The idle goes UP and DOWN, up & down, up & down, does anyone have any suggestions, maybe the choke assembly or inricher? 

I couldnt get a bigger carb for my scoot, so I just removed vacuum lines and I connected the vacuum from the intake manifold to my pod filter, now the engine is getting more air and I just up jetted the carb to compensate for more air and it works great

[scooterted]

You can get a 20mm carb. Worth a read --> 49ccscoot.proboards.com/thread/11639/real-20mm-carburetors-fakes-pictures

[handyman]

thanks for the excellent advise, I will research before buying

[90GTVert]

Surging at idle would make me check intake/vacuum connections and for cracks in the intake or hoses first.