Hard Starting and Idle shenanigans - NT Carb

The Nickster

New Member
Local time
4:07 AM
May 17, 2020
I've tried a variety of throttle and choke combinations....and idle settings. What has worked is the idle speed screw about half a turn out and 2/3 choke. Starts in the first or second attempt every time. Throttle cable adjusted at lever and cap so that there's just a tiny bit of slack (see: small; so basically both are turned all the way in). I've taken the carb apart and everything looks in order. When i turn the choke off i notice a change in RPM, so i think that's "working" (but not). This is during the break-in period so I'm 8oz oil to a gallon.

So after it starts, the idle is way too high (not like "blow the engine" high - but higher than you'd want it). So then I back the idle screw back out and it runs fine for the duration.

So I guess i can do this little dance at startup (once it's warm, it starts again without adjustment), but it seems a bit ridiculous (and hurts what little pride i have...) ;-)

Do i need to adjust the c-clip on the needle up or down? Everything is "seated" properly in the carb, throttle rolls smoothly and snaps back nicely. Not a lot more going on with this carb - intake manifold leak?



ps - sorry if i didn't use the right words - first time poster/m-biker. This is a brand-new kit build - straight out o the box
Nickster, Welcome to MotoredBikes..... The smarter people then me will be here soon to help you. :)
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It appears the above described situation my have been related to break-in period - after about half a gallon of riding, starts without the idle screw dance. Anyway, in case anyone else runs into it; my experience.
I had a motor that lasted for along time at 4oz of regular air cooled 2 stroke oil the cheap stuff. It was like the energizer bunny it kept going and going.
thanks for the input. The majority of sellers recommended 7-8oz for the first 100-200 miles. Maybe it's as much about how you ride it during that period as the mix. I'm not feeling the need for more "performance" ;-)