Originally Posted by rodmuzwa
Thanks for that. So does that mean its simply a swap over and good to go?
Essentially, YES! Your replacement slide is essentially, "DIRECT EXCHANGE."
The 22-cent mod consists of two elements; drilling the vacuum port in the slide to 7/64" diameter (in hope of enhancing throttle response), and shimming the needle (with one or two approximately 0.030"-thick washers, to fuel-enrich the air/fuel mixture from low through upper mid-range throttle excursion).
Why fuel-enrich the mixture when dominated by the needle and neelde jet? Some believe the mixture is sub-optimally fuel-lean as-built, to insure conformance with emissions standards.
Then again, I know of an '08 KLR650 with 55,000 miles of extensive northern and western hemisphere travel, with an absolutely stock-configured carburetor, and a happy rider! (Not I; but an inmate whose technical opinions I value.)
The idle mixture screw adjustment (proposed starting point: 1.75 turns out, at sea level, stock engine) seeks to compensate for factory adjustment, allegedly skewed for emissions compliance.
Your bike, rodmuzwa; whatever works for you, WORKS!
Congratulations on scoring the Harley slide.