To my 40 Instructables subscribers, and anyone who stumbles across this and likes it, be sure to take a look, as much of what I write isn't quite right for an Instructable.)
Bikes are perhaps the greatest human invention of all time.
They get you from where you are to where you want to between 2 and 5 times as fast as you could walk there, but they use absolutely no fossil fuel or external energy what-so-ever, which means they have basically no environmental impact and no operating costs beyond the original manufacture and purchase.
However, if you are not already a "bike person", the amount of choices in type and brand and size and accessories can be overwhelming. If you buy new from a local bike shop, the salesperson will most likely walk you through the process of deciding what will fit your needs, but if you want to save money (and further reduce your eco-footprint) you should really buy everything you possible can used.
So, for the beginners who know just about nothing about bikes but want to get one from Craigslist, or perhaps a thriftstore or yardsale, I'm going to break down for you exactly what to look for and what to avoid.
Step 1: About me
I began riding regularly for fun and transportation in 1992, when I was 12. The next year I began riding to school every day, so that I could keep the bus money for other things. In high school, in addition to daily commuting (to school and internship) and weekend rides of 40-100 miles, I began annual 4 day trips down the CA coast with a group of teachers and friends. After college I went with the couple that had organized those annual rides from San Francisco to Puerto Vallarta Mexico, and went solo from there along the coast to Acapulco and then North to Mexico city (over an 8000ft pass) for a total of 2800 miles over 2 months. When I returned, I took a job as a bicycle messenger. I eventually ended up also working as a messenger in New York City.
In 20 years of serious riding, I have had a bmx bike, a steel touring bike, a British internal-hub drop-frame from the late 60s, a carbon fiber racing bike, an aluminum mountain bike, and two folding bikes, all of which together I paid a grand total of $450 for (of which $400 was the carbon fiber road bike).
Eventually I returned to CA where, for the past 5 years, my primary job has been as a hauler (mover, and handyman) which involves picking stuff up that people don't want anymore, and then finding new owners for those things. This involves either selling or giving away anything which is still useable (which is most of what I pick up), frequently on Craigslist.
My second job for the past 5 years has been as a mechanic in a tiny bike-shop of sorts, the Bike Station, whose primary service is FREE secure valet attended bicycle parking, but also offers relatively low-cost repairs. Because we don't sell new bikes, and because we never turn anyone away for lack of bike quality, I have been able to work on a great variety of bikes, of all types and ages and cost levels, which is rare in any one shop.
(My third job is a reserve for the Coast Guard, but that isn't relevant to this at all)
And now... on to the content!