So we're headed off Friday, me and another 60-year-old guy, to ride our bicycles 3,100 miles across this great nation of ours. We've planned a trans-southerly route starting Sunday from the beach in San Diego to the salt marshes of Savannah, Ga. — avoiding cyclophobic stretches of Texas if possible.

Why the journey? For starters, we're both older than the chief justice of the United States. What exactly are we waiting for?

This projected two-month trip has been sold to our families and friends as a kind of pre-geezer vision quest; a life-stage spiritual mission with a purity of purpose usually associated with postgraduate Mormons. That's been our story. But it also is, true enough, about two bike-riding buddies who think it would be way-cool to explore far-flung parts of the country at pedaling speed, groom only on an as-needed basis, and generally live the serendipity of an extended, free-form tour. The time seems right.

My riding partner is Will Fifer, a custom furniture-maker and proprietor of Blue Sky Galleries in northeast Minneapolis's Northrup King Building. We have known each other for roughly 50 years. Since the Johnson administration anyway. Until now, we have woven into each other's lives as kids, in college, and as middle-aged parents whose kids went to elementary school together. We have ridden thousands of miles, in both glorious and dreadful conditions. We're cute when we bicker, people say.

We will file blog posts on along the way, chronicling a journey that is certain to have considerable rewards and, just as certainly, some witheringly stupid and dispiriting days. Oklahoma is 550 miles wide, by the way.

Not alone

Transcontinental bike touring is actually a thrillingly accessible expedition. Of course, not an easy trip, and not a trip to be approached casually. But with some preparation and determination — and a decent bike — most any actively ambulatory person can make a go of it.

In fact, legions of people are packing up their bikes. Consider Adventure Cycling Association, a 35-year-old nonprofit in Missoula, Mont., that supports bicycle touring. In a given year, almost 500 people buy the map Fifer and I are using from San Diego to central Arizona. Last year, almost 1,200 people on bike tours stopped by the association's office — more than 10 percent of them from other countries.

Heck, go to the website — please. It is an enormous and engrossing trove, including more than 9,600 daily journals (!), most with photographs, posted by people on long-distance trips over the past decade all over the world. Does New Mexico sound tough? Try Kazakhstan. Many people have.

Some set out on bike tours packed like mules, camping and cooking along the way. Others just want to show up and ride, so they pay outfitters to handle the logistics and their gear. Some people convince friends to follow them in an RV. Some people, and this is our plan, stay in motels, hostels and dorms — really, wherever — and bring along light sleeping bags and bivy sacks for emergencies.

The liberty of independent touring does have risks. People get stranded. You hear a lot of stories of those who, through some random confluence of weather, bent wheels or bad luck, end up in the middle of nowhere at nightfall. They usually pull over and take refuge behind the most welcoming rock. But there also is this: Many years ago, on a bike trip in high school, a friend and I pedaled our 10-speeds into Spooner, Wis., just ahead of an ugly storm. We asked a policeman if he could suggest shelter. He said, "Would you like to sleep in the jail?" We each got our own cell, and the overnight deputies shared a birthday cake.

Setting out

The working plan is to review daily mileage and look for charmingly economical accommodations along the way. Some days we'll splurge; some days we'll have no choice at all. On return, we should be prepared to write the definitive travel guide, "Checking Into Hell: America's Most Dangerous Motels."

Part of the adventure is this fact: Fifer and I have never spent more than two consecutive nights together on a biking trip. How will dozens of consecutive nights work? I am completely optimistic. But I am also prepared to request mediation when our wives fly down to visit us in New Orleans.

The trip's, uh, nuts and bolts? We are riding two kinds of bikes — mine is a steel touring bike; Fifer's is a titanium cyclocross model (see sidebar for details). Since training has been largely indoors this winter, we will have to ride ourselves into shape. Our gear has been pared down to essentials. Our bikes were disassembled, boxed and shipped ahead of us to San Diego. If all goes OK, we'll reassemble the bikes Saturday and leave Sunday morning from the Pacific Ocean.

We'll be in San Diego, headed for Savannah, by calculation and happenstance. Prevailing winds supposedly run west to east. Savannah became a natural destination because it's lovely, and we have family and friends there. A March departure from San Diego allows us to cross the southwestern deserts and deep southern countryside in what could be accommodating spring temperatures. From the Pacific to the Grand Canyon, we'll be on two of Adventure Cycling's established routes; we'll freelance a route from northern Arizona to the Louisiana's Gulf Coast, then pick up another Adventure Cycling route through Mississippi, Alabama and Florida, before diverting north to Georgia.

The route

Our path is wildly eclectic. One that, we can't help but notice, starts Day 1 with a 4,000-foot climb into the Laguna Mountains, and in the days thereafter includes several hundred-mile stretches that lack towns. We're rerouting around Texas to avoid its vast geographic tedium and its widely alleged cowboy harassment of cyclists. We also found more attractive options. (Midland or Taos? We're doing Taos.) The hope, too, is to average a relaxing 50 miles a day.

We have some rules for our ride:

• Stay together on the road. This is not always easy. If one person stops to photograph flowers or chat with a farmer, and the other person is in Zen cruising mode, the two of you quickly can be 10 miles apart. That's not usually a problem. But, for example, last summer Fifer and I rode to northern Wisconsin. On the second day, my rear tire went flat. Fifer was 150 yards ahead, oblivious, and didn't hear me yell, "Hey! Fifer!" I fixed the flat and didn't catch him until lunch — 35 miles later. What if I had totally broken down? Or face-planted in the ditch? So the rule is: If you haven't seen the other guy in a while, stop, wait and head back to find him if necessary.

• No rest stops at the bottom of hills.

• No tailgating, especially going downhill.

Other than that? We'll figure it out along the way.