Not sure but different rotors and different size bearings come to mind.
Springer, you are right. These rotors are wheel mounted and there is no other rotor size available other than 300 mm. A twin cam caliper found on 2007 ~ down to 2000 will not work. You need a way to have calipers that will work on a 300 mm rotor. The rest is easy.
I bought the installation kit, that way I have a complete easy on wheel if I need to switch.
Hope you don't mind if I chime in on this one. When I got the black Agitators for my black bike last year, I too bought the install kit. Waste of money. They give you all kinds of crap you can't & won't use (because the kit fits V-Rods also) when you can just go buy the bearings & spacer and save a good third or more. Like, ugly rotor bolts you know you won't use, a rubber valve stem (wowee!) because the metal one ain't workin', I mean really! I just ordered a chrome set for my Roadie (f&r, tires, rotors) and it was like half the install kit price by going with the bearings & spacer. The money I saved will get the tires installed by my favorite indy, I do the bearings myself. I learned my lesson.
At least this time I didn't get the stupid question from the parts monkey why I didn't want them to install the whole deal. Why? Cause I'm not stupid and I don't want it all F'd up.
Been following this thread since the begining and pulled the trigger a couple weeks ago.The front came in last week but the back wheel kit is on back order so now it sits and all i can do is wait.