MY brother and I just got done riding from Canada to Pinedale on the CDR. 90% of the road will be easy for those big bikes but the last 10% will be a serious challenge. Your best bet will be to keep them as lite as possible also in Montana be ready to deal with a 38% grade terrain, lots of slippery gravel roads, and some very technical rock climbing sections. Also your daily miles seems a bit optimistic, You will not be able to travel as fast as you want since a lot of CDR roads/trails are used by ranchers and you will have to travel slow around corners, unless you want to get wiped out by oncoming traffic. Which almost happened to us in Montana when a honda accord came flying around a corner at us in Bannack state park.
We rode dr650 with very minimal kit through all the tuff bits. We are currently doing the Utah back country route and will eventually make our way to baja then even further south. Enjoy the ride, be safe.
ps. Stop at the Wise River Club for some great food in Montana
1108pedro screwed with this post 06-24-2012 at 12:01 AM