There has been mention of using a bike as transport. Like anything else, the body has to be conditioned for such endeavors.

The reason I say this is because after a few years of only, short mountain bike rides, I am getting back in longer distance riding and found that although I am in good physical condition, this did not initially translate to good bike riding condition. It has taken pretty much the whole summer of part time riding to get to the point that 30-35 miles in a few hours time and in very varied terrain (uphill/downhill, pavement, gravel/dirt trails) is now achievable without suffering with sore legs, sore butt, numb hands etc. To ramp up to perhaps double that distance or more per day will take awhile yet. And I would think that for anyone considering using a bike as a vehicle under your scenario that they really get out on the bike and get a lot of training miles in.

On the same subject, the weather has peaked here into the high 80's to low 90's F. In the last 2 days of riding, I consumed 4 liters of water each day in a relative short riding distance. The OP probably lives in a much hooter summer environment and needs to consider that daily water consumption on longer riding days can possibly be 2-4x higher for one or more people. That is a lot of water to plan for and refill as you go. This means having multiple methods of water filtration and treatment such as a Katadyn filter and plenty of water treatment tablets such as Aquatabs or Micropur.