China ATV Carb Question
 

Model ATA50 TaoTao?
Green Panther 110
Looking on the Web to buy a carburetor and I see a lot of parts houses selling one carb that fit from a 50cc to a 125cc engine. How does that work. What about jetting?
Example:

20mm PZ20 Carburetor Carb for 50cc 70cc 90cc 110cc 125cc ATV Quad Sunl Tao Tao | eBay

This carburetor looks identical to mine on the outside but what about jetting on the inside?
Will one size fit all?

I've been pondering the same thing bump

That is why you should clean out your old carb and put it back rather than buying a new one which will need setting up to suit your bike. It is always quicker, easier and cheaper to clean out the existing carb.

I found this site helpful. http://outsidedistributing.con

are you deef and dumb the question was if one carb dos 50-125 are the jets adequate to each cylinder size

I'm thinking this is not the best attitude in getting a question answered. Chinese carbs are cheap in cost anyways. Buy it and look at your original to what the new carb jet has. Jets don't go bad, they just need to be cleaned. Use whatever works best in your area altitude.

I have cleaned out well over a hundred ATV carbs and have only needed new parts in a handful of them. My point was don't buy a new carb because the jets probably won't be right, or any adjusters set for your machine. I've had carbs with the stale fuel inside turned bright green as it has dissolved some of the brass, once the carb was clean, the bike ran fine.

yip sorry my bad but the question isn't answered how can one carbi work on a rang of engine size and function properly on all of them ?

You'd be surprised at smaller carbs on larger engines. They do still work. Once you get into 250cc and up, the carbs are much larger.

Not saying it's the best practice, but you'll see just that on a lot of chinese atv's.

If it's any help in understanding how one carb can fit different machine,take the Polaris 250,300,400 atvs. Basically they can use the same diameter carb,but the jetting and jet needles are the main difference. When carbs say it's a 20 mm,22 mm,etc it's not in the external dimensions of the carb but in the open area called the venturi where the carb is measured.That's why it's possible for one size carb that can be used on several different models in engine cc size.Again the main difference is in the internal jetting sizes of the carb and also needle valves(needle and seats) have different flow rates depending on the machine it's used on. Some needle valves may have say a 1.5 gfm (gallon flow per minute) for a smaller engine versus a larger needle valve(2.0- 2.5 gfm for instance) to allow a faster fuel delivery to the carb bowl for a larger engine size. These are sometimes marked on the bottom of the needle valves. Here's a video on the venturi of a carb. Hope this helps.