The new NT
is marginally different internally - the needle is slightly shorter with a bit more of a taper, the jet is a touch larger and the slide itself is also a hair bigger - enough so the slides don't cross over between carbs.
All this I noticed when I tried to rebuild my old carb w the guts outa the new one...
Having said all that - there still isn't enough of a difference to consider it a "performance" carb, it's just a lil better for the 66cc than the one it used to come with lol I would definitely try the CNS! Yet for the price it
is bordering on getting a real carb - like the Dellorto I'm considering:
PHBG 16mm AS Carb (Clamp On Style) 2 Cycle [D0-2511] - $84.20 : Dellorto Carburetors, And parts for you.
*shrug* It's up to you lol, I've still not made up my mind