Buying a bicycle can seem complicated. But it really comes down to a simple consideration: what would you like to do with the bicycle? After you can answer that, then "buy the bicycle that you love."
Bicycles come in many flavors, but I will limit today's selection to three general commuter groups (other good bikes include recumbents, folders, and ebikes). Road bikes are nimble, light bikes designed for speed. These can be the bicycles that cyclist race or tour on, designed to be light and quick with minimal drag. They are not the best for carrying racks or taking abuse. The rider sits in an aggressive position tucked down aerodynamically.
Hybrids, cycle crosses, and urban bikes are popular choices for surviving the slings and arrows of outrageous urban commuting. These are more robust than road bikes, can take more of a beating, have somewhat bigger tires, and can carry racks. They are bigger than road bikes, but not as big as mountain bikes. The rider sits more upright, causing more aerodynamic drag. Brakes and shifters tend to be very accessible so that the cyclist can make quick moves.
Mountain bikes are the monsters of bikes, with big frames, big tires, and shock absorbers. Designed for off road adventures, many people like them for commuting. The bicycles come with bigger tires, making for a more comfortable ride, and the cyclist sits in an upright position. Mountain bikes feature lower gears that can help pedal up big hills.
Bicycles are made out of various materials. My original bicycle was steel. It was tough, heavy, and absorbed vibrations from the road. My current bicycle is aluminum; it is lighter and wonderfully designed, but the aluminum is stiff and transmits road vibrations into my body. Unlike steel, aluminum does not corrode. Carbon frames are big for high-end road bicycles. They are light and tough, but uncommon among commuters. While aluminum is popular, there is a big movement back to steel due to both its strength as well as the smoothness of the ride.
Generally there are two types of handlebars: drops and flats. Drops are your classic ten-speed bicycle handlebar with the curled down bars, allowing the cyclist to drop down and become more aerodynamic. Flats lend to a more upright position, with brakes and shifters up on the flats near one's hands, allowing the cyclist to be in an alert position to watch traffic.
Racks: Good road bikes are designed for speed and will not necessarily have eyelets in order to attach racks. If you don't have a rack for bags, then all your stuff goes in a backpack on your back. Urban bikes and hybrids will support racks, so that weight can go on your bike frame, not you.
Tires: The bigger the tires, the smoother your ride will be and the tougher the tire itself. Small road bike tires like narrow tires are faster but not good for off-road or potholes. Smaller tires are more likely to get flats. Medium tires are tougher and can take a beating, while not slowing down the bike too much. Larger tires are mountain bike tires, which can take a beating and might help out in bad weather conditions like snow or rain.
Another consideration is how good is your parking. At my office, we have great parking in a secure garage. That permits cyclists to ride some nice bicycles. If however you have to park you bicycle where there is a risk of theft, think about getting a less attractive used bike. There are many shops such as Phoenix Bikes that sell quality vintage bikes that will give you a great ride but wont scream "steal me." Buying used can also mean buying a quality bicycle with good components for less.
Getting the correct bicycle size can be a challenge. Ebicycles has an excellent bicycle frame size chart to help you use your inseam and your height to get a good estimate of frame size (it is only an estimate). Some bike shops will give you a professional fitting, starting with frame size and making adjustments for seat height, stem length, and crank size. Some sales people are wonderfully helpful and will help you get the right size (others are just saying what the marketing has told them). Check reviews of bike shops and be careful. A poorly fitting bicycle can lead to back and knee pain. Get advice and take the bicycle for as long a test ride as possible.
Bicycle stores like car stores are married to brands. One store will sell one brand; another store will sell another. Visit lots of stores and try out lots of brands. Each bicycle is a little different and will fit you a little different. This is called geometry. In includes seat post angle, head post angle, the height of the bicycle, the length of the cranks, and the length of the top tube (how far the reach is to the handlebars). Two road bikes made by different companies are going to feel different to you. They may be the exact same size, and one fits you like a glove and the other makes you uncomfortable. Try out lots of bikes, taking them for good long test rides.
Do your own research. Read material online. Find some cyclists friends and ask lots of questions. Read reviews.
Accessorize: Additions that you will want to think about: helmets, lights, lock, reflectors, gloves, and bags.
What does all this add up to? Buy the bike you love. When I bought my bike, I wanted a tough urban bike, that could take abuse, fit me (I am tall), kept me in an upright urban position where I could watch traffic, and could carry my gear. All of this led me to a Cannondale Bad Boy (a similar bike is currently the Specialized TriCross). My friend, working through the same thought process, ended up with an All-City Space Horse. It is a steel road bike, giving her strength, speed, a smoother ride, fenders for bad weather, and racks for her gear. Another younger friend who has a need-for-speed went for a light, nimble Specialized Allez road bike.
People have love affairs with their bicycles; go out and find the bike you love.
- Bicycles: How to Choose, REI
- How to Buy a Bike, Bicycling
- Bike Buying Guide, Consumer Reports
- How to Buy a Bike, Potomac Pedalers