This video will show you how to tune your NT carburetor to improve your engine’s performance:
How To Tune NT Carburetor for 48cc 50cc 66cc 80cc Motorized Bicycle
Just a few things to also check on as well:
- Check your intake for any debris clogging it up or in the carburetor itself.
- Check the float and float bowl. If the float is full of fuel, it's not regulating the fuel properly so get a new float.
- Check the float bowl mechanics. Make sure the plunger is installed properly and it's not sticking or stuck.