Although this article is actually about putting a 2008 wheel on a 2002 bike, it will give you some insight on the bearing differences between the 2008 wheels and previous years. This article is from yahoo answers. Hope this helps.
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In 2008, H-D went to 25mm bearings on almost all of their wheels. (I think the lone exception is the Springer) If it were anything other than a Touring vehicle you would be out of luck since they made changes to the depth of the bearing bore to account for the fact that the 25mm bearing is narrower than the 3/4" and 1" bearings (which have the same width).
As it turns out, for Touring vehicles they put a spacer in the bottom of the bearing bore, underneath the bearing, in order to get the right spacing.
So, what you need to do is:
1) Order replacement 1" bearings and sleeve (the long spacer between the bearings inside the wheel) for your 2002 vehicle. If you want to re-use the sleeve from your current wheel, that's okay, but do not re-use the bearings since they will be damaged when you pull them from the wheel.
2) When you pull the bearings from the 2008 wheel, pay close attention to which side has the thin spacer under the bearing. The side with the spacer is the 'primary' side. (primary side is also vehicle left)
3) Follow the bearing installation instructions from the service manual to install the new 1" bearings and sleeve, making sure that the 'primary' bearing is fully seated in the bore.
Edit: you don't have to change the rotors