YFZ hubs are shorter.
If you swap over to YFZ spindles you cant use your banshee hubs unless you get some short castle nuts , OEM wont align cotter pin holes.
yes as long as the piston shaft is not corroded or pitted, if it is it will eat the new Oring.
if the piston shaft is bad you will need to replace the piston ,or you can cut it off and tap the hole for a pipe plug.
I have some new and used drag - TT-FT tires.
priced per pair shipped to the East Coast ,anyone west of the central time zone add $20
New 20-10.5-10 Hoosier slicks $195
New 22-11-10 treaded Hoosiers $210
new 18-8-10 American racers $175
used 19-10-10 American Racers 90-95% $145
used 18-8-10 Hoosiers 85-90% $120
used 18-10-10 Hoosier Tri Tracks 85-90% $135
also have a set of barely used 22-10-10 Maxxis 4-snows on oem YFZ wheels $150.00 shipped.