I'm planning a tour with a buddy this summer/fall, and was curious if anyone had any information regarding crossing Mexico back into the US from Mazatlan.
Currently, we are planning on starting in Jackson Hole, WY (following a thru-hike of the Wind River Range) and heading up to Glacier NP, and from there heading west to Seattle. Once in Seattle our route will take us down to San Diego, where we hit a potential crossroads. Currently we are planning on heading to Key West, FL, by way of Taos, NM. But I am also curious about continuing down Baja California, ferrying over to the "mainland" and cycling up through copper canyon back into the US where we'd continue on our way.
Okay this is pretty vague but a couple of friends did this one about twenty years ago. They went the other way, Copper Canyon first and Baja after.
They said some of the roads on the mainland side were poor quality and lots of chaotic traffic especially close to cities. I have heard that the ferry schedule can be a bit erratic. You can't be in a big hurry, but , hey, its Mexico.
The Baja California roads are okay, I've driven them. The main highway can be pretty narrow, and there are cows on it at night, but I don't expect you will be riding at night, anyway.
My friends did this without speaking any Spanish and without a decent guidebook, just gas station maps and talking to other travellers. Where there is a will there is a way.
Sounds likea fun trip. Hopefully somebody else will have more specific information.
I haven't biked in northern Mexico, but I have biked in central & southern Mexico, and the roads were pretty good. The closest I got to Mazatlan was Jalisco state. Mexico had a lot of surprises, nearly all of them nice surprises. Also, if for any reason you don't want to bike all of the route you described, Mexico is one of the easiest places in the world to put your bike on a bus.