I've crossed at Mexicali with no problems too, which might be more convenient for you, coming from Flagstaff. From there, the ride is pleasant, and not crowded down to San Felipe. You can either ride some dirt from there thru Coco's Corner and on to Rt. 1, or backtrack on the pavement for a pleasant ride to Ensenada on the West coast. If you head down Rt. 1 from Ensenada, make sure you fill up with gas around El Rosario, and any Pemex station after that.There is one at a rather expensive hotel in that stretch, but the pumps were out of order the time I rode that way. You'll also find gasoline vendors at the turn-off to Bahia de Los Angeles. Otherwise it's a long ride to Guerrero Negro, and the Pemex there. Try the fish tacos at Danny's in Mulege. Also the pescado al mojo de ajo at Scott's El Candil in Mulege. The ride south of Mulege along Bahia de Concepcion is speco and fun.