I've read a lot about a Sportster needle in a stock Dyna CV carb is supposed to sharpen up throttle response.
I have a needle with N9EY engraved on the neck which I believe came from an 04 Sportie,anyone know if that'll work with my 03 FXDX?
I know it'll use more gas but I don't do big miles so not too worried about that.

 

Don`t bother with that needle, there is nothing special about it. The Sportster needle you want (N65) is the one used on the 1988 model, no longer available from the dealer, but you can get one from these guys:

http://www.cv-performance.com/cvp-n65-needle/

 

Or get the one made by cvp for the big twin. It is the n65 tweaked a little for the bigger 1340 engine. Not sure what that means, but....YD