AussieSteve
Active Member
it mostly runs bad idle-3/4 throttle
That sounds like the slide needle is too high, but you adjusted correctly - when the needle is at it's lowest, the mixture is leanest.
The main jet still has a fair effect on mid-throttle as well as WOT.
Do a plug chop at WOT and if it's rich, change the main jet and that will also lean out the mid-throttle mixture.
I was thinking about checking the float level but not sure if that would make a difference anyway
Yep, that could make a difference - the float level should be 21mm from memory. See NT Carb Tuning Basics for a bit more info on that.
There's also a link to a good illustrative video of 'four-stroking' that might help.
Worst case scenario is I buy an aftermarket carb that allows mixture setting.
I'm considering that myself for better performance, but it's possible to get the NT carb pretty well tuned with a bit of f'ing around.
Did I have it right adjusting the clip like I did??
Yes, see above.
Moving the clip up lowers the needle into it's seat, reducing the amount of fuel in the mix and vice versa.
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