Unless something has changed in the past year or two, you may have ot go to a bias tire to get a size that is comperable with the XC.
I don't know what all the bias is toward bisas tires, but in some circles it is rampent. I have heard good and bad for the 180/65 16 that Dunlop makes for the HD. Michelin has made an offering that probably would be a better choice.
Let us know how you end up and how you like your choice.