Hi Dave; your trip into Copper Canyon land [generic for all the Barrancas de Cobre]will be a trip to remember. Batopilas town is at the bottom of Batopilas canyon, one of 5-6 major canyons plus several smaller side shoots. The town lies lower than Creel by at least 1200 metres and is quite warm in July with little rain if any.
The road is hair-raising at any time,so you must exercise utmost care and have exellent brakes on some 28 hairpin curves from the rim to the Batopilas river.
A motorcycle is ideal to get through. You will gain confidence and awe once the trip is complete; I wish you best of luck. And do yourself a favour - learn some Spanish; it will pay off.
My knowledge and experience was earned by two trips. One in 1959 touring from Canada through most of Mexico to California on a 1958 350cc Royal Enfield. You can easily do it on a 1100cc. Then I took a three months hike thru Baja and up into the Tarahumara-land in 2003. Couldn't have been much colder in snowy highlands;I just escaped hypothermia and freezing my ball(bearings)off. Good luck, Jorgen