[Little Wing]

Thank you!! She only has 55k miles on her and I just want her to last forever

From what I've read, the 18" wheel is the best (and most economical) way to go.
Both the 21" and the 23" require major neck (rake) modifications, and you're very limited on tire selection.
The 18 x 5.5 wheel requires the same size tire as stock harleys so availability is better.
I'm sticking with the Dunlop AEs when I make the jump.

 

[Little Wing]

It looks like a 21” but it’s hard to tell with the shin fairing and it looks like it’s lowered a little..? Looks hot regardless

that's Rob Murphy's bike. He did a video on the install and describes all the nuances.
he lowered the front 2" and he also has air suspension so it sits real low.

 

[Little Wing]

If I already have the 21” tire do you think there would need to be modifications to jump to the 18”?
awesome! Thank you

I don't know, but Dave at Native Custom Baggers 269-276-9200
answered every question I had.
They can address air ride suspension and all the possibilities, too
Rob's bike is an 18" front tire that has been lowered 2" and aired down on the picture.