Ingredients of a Good Bike City

What would Jesus ride? Photo Credit: backalleybikes.wordpress.com

The idea of identifying "the best bike city in America" (or something along those lines) is one that pops up with a fair degree of regularity. But what exactly does it mean? Most traditional rankings look at certain urban amenities that support the enterprise of bicycling, with some taking into account slipperier factors like observed biking levels or motivation. In fact these two approaches are linked in a complex relationship that makes simple list-making tricky. What we're really looking for is the capability to flourish on a bicycle: what cities enable the ability for anyone to employ well the bicycle to pursue their goals of living a good life. A few thoughts on some relevant bike city elements:

1. Bike Lanes: Clearly these are nice, and make everyone feel safer. The amount of bike lanes is easy to measure and easy for politicians to brag about, but what's more important is the quality. Is the paint fading? Do they disappear and pick up again on the other side of the street? Are they separated by medians or parked cars, or do they hug the edge of the road, forcing cyclists to make the no-win choice between exposing themselves to either dooring or collisions from passing motorists. Consistency in bike lane design is massively undervalued. Do they go along sensible, efficient routes? Also, do they get cleaned? I've personally been excited for the construction of a new bike lane only to see it fill up with gravel, broken glass, and puddled water. Upkeep matters.
2. Road Quality: This doesn't get a lot of attention, but boy does it matter. Smooth, well-paved roads make biking dramatically more enjoyable. Safer too: fewer obstacles in the road means a less-erratic riding line. Big east coast cities are old, with crumbling infrastructure. Younger cities experiencing population booms out west probably have better roads.
3. Density: In the broad scheme of things, this is the most important factor influencing the quantity of cycling. Simply put, if you live in a rural area, you won't be able to substitute biking for driving due to the large distances between stuff. But average population density can also be misleading; what really matters is architectural density. Los Angeles has an impressive average population density, but the road-centric urban form makes cycling less appealing. Philadelphia has a tight, cramped city core that limits the speed and craziness of drivers, making cycling dramatically more enjoyable. 
4. Weather: The influence of weather on cities is tricky to measure. One can say that, all thing equal, warmer cities are better for biking. But in reality there are simply not enough big cities in each climate to cancel out all the effects from other factors like urban form, history, culture, politics, etc., so we'll never know.
5. Norms: Do drivers and cyclists have a respectful or adversarial relationship? Do motorists and pedestrians regularly occupy bike lanes? Norms receive a lot of attention because they play into the "style" and "identity" of notorious bike cities like Portland and Amsterdam. No doubt this factor exists to some degree. But much of what we assume derives from some special cycling je ne sais quoi actually comes from other factors. The more people who cycle, the more well-trained motorists and pedestrians will be to notice them. Variation in local traffic enforcement rules also structures the decisions of motorists and cyclists. 
6. Psychic Torment: Perhaps the best way to identify great bike cities is to look at the actual experience of riders themselves. For some, cycling is terrifying. For others, it's a delight. Why not just ask people!? The popularity of cycling as measured by public opinion polling surely varies by city. Throw in some survey questions like, "do you wish you could bicycle more, less, or about the same as you do now?" and you've got the makings of a sophisticated account of which cities are great for biking. A benefit of this approach is that it incorporates both the supply of bike amenities (like density and bike lanes) and the psychological profile of cyclists. Some hipster bike salmon are going to ride on any road, no matter what--do we really want to count those people when considering the best bike city?
7. Motivation: On a related note, should considering why people bicycle play a role in identifying great bike cities? Some people choose to cycle for recreation or exercise. Others may choose not to cycle because they're unhealthy, old, or obese and it's physically strenuous. Big east coast cities have tons of food delivery people zooming around on bikes for a paycheck. Some ride bikes because they're poor and can't afford other options. Underlying this is a deep question about what drives people's transportation decisions. Biking exists within a world of trade-offs between walking, driving, and public transportation (and their respective inputs like public transit quality and gas prices). We can't just look at cycling in isolation. If we did, we might get the perverse result of a good bike city simply being one where public transit is terrible and driving sucks. When we're looking for the best bike city, does it matter that people adopt cycling for the right reasons?

The bottom line is that there's no clear way to identify the best bike city. The supply of bicycle amenities isn't something that you simply maximize to win the title. Different people bike in different ways, for different reasons, and you have potential confounding factors like demographics: young, fit people cycle more, so cities with more of those people record higher rates of cycling compared to older, fatter cities.

Perhaps the best approach for evaluating different cities and their relationship to cycling is to compare them to national averages. Presumably some demographic groups (race, income, education, age, health, etc.) have higher rates of cycling in some cities than others. By aggregating many different comparisons, you could see which cities "punch above their weight" so to speak.