carburetor

there is no "best" oil. I prefer synthetic or semi-synthetic because I hate exhaust smoke. But use regular oil till its broke in so the rings can seat well.
Most people set the needle at the lowest position (clip on highest position) before they finally get tired of that crappy nearly non-adjustable carb (without an idle circuit) and get a good carburetor
 
Nothing wrong with the standard carburettor. It's simple and easy to set up, and it gives good results in operation.

Having said that, my preference is a Walbro style diaphragm carburettor attached to a Rock Solid Engines reed valve intake.
 
what's wrong with the NT carb:
1) it has no idle circuit
2) there are no other needles available for it with different angles of taper
3) it often develops air leaks where it connects to the manifold
 
If the carburettor is jetted correctly and has no manifold to carburettor air leaks, the standard NT carburettor gives an acceptable idle and an acceptable transition to wide open throttle.

Alternative needles are not required with this type of carburettor and venturi bore size, because the engine spends little time at part throttle. Even when the engine is used at part throttle, there is enough adjustability in the positioning of the needle via adjustment of the e-clip.

An o-ring placed in between the carburettor and the intake tube, takes care of any air leakage that might make it's way past the carburettor clamp.

The issues you raise are easily fixed.
 
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A common complaint is that when the needle is set right for mid throttle acceleration then the jetting is off for full throttle power.
Also, how do you "easily fix" the missing idle circuit? answer: you don't
 
You simply jet the carburettor so the engine is running on the very edge of 4-stroking at max rpm of 5,000, then place the needle as low as possible or seen another way, placing the "E-clip" as high as possible on the needle, and it's job done.

You will have a carburettor that operates flawlessly at idle and transitions flawlessly when you snap open the throttle, and runs reasonably anywhere in between.
 
2 strokes run best at high rpm with the jetting just a trad richer than what causes it to seize, not slightly leaner than what makes it 4 stroke
 
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