I did Trans-Canada, that was 5000 miles and took 76 days. I can very strongly recommend going from West to East as this is the way that the prevailing wind goes. Going from East to West in the US adds about a week and will mean that you will almost constantly be going into a headwind. This can be quite demoralising which isn't something that you need on a trip of this scale.
Other general advice is not to plan too much ahead. We only ever though up to three days in advance and were always happy to change our plans according to what happened. I understand that most states have a published list of campsites that you can pick up at TI centres. Usually on entering a province in Canada we would get straight to a newsagents and grab a province map (lighter than one for the whole country) and then get the campsite list. The next day was usually given a short, medium and long distance option (occaisionally you will have no choice but to go long). Take a Rough Guide or a Lonely planet with you so that you don't miss too many diversions along the way. Seek local advice about the roads as well. Quite often the maps can be wrong and ones marked paved will no be. Keep an eye out behind you for RVs with 1-800 number splashed across them. These are rental RV's and most drivers don't know the size of them. Be prepared to pull over and give them good berth if the road doesn't have a shoulder.
I did Trans-Canada, that was 5000 miles and took 76 days. I can very strongly recommend going from West to East as this is the way that the prevailing wind goes. Going from East to West in the US adds about a week and will mean that you will almost constantly be going into a headwind. This can be quite demoralising which isn't something that you need on a trip of this scale.
Other general advice is not to plan too much ahead. We only ever though up to three days in advance and were always happy to change our plans according to what happened. I understand that most states have a published list of campsites that you can pick up at TI centres. Usually on entering a province in Canada we would get straight to a newsagents and grab a province map (lighter than one for the whole country) and then get the campsite list. The next day was usually given a short, medium and long distance option (occaisionally you will have no choice but to go long). Take a Rough Guide or a Lonely planet with you so that you don't miss too many diversions along the way. Seek local advice about the roads as well. Quite often the maps can be wrong and ones marked paved will no be. Keep an eye out behind you for RVs with 1-800 number splashed across them. These are rental RV's and most drivers don't know the size of them. Be prepared to pull over and give them good berth if the road doesn't have a shoulder.