Chapter 1. Bike 101
Bicycles are big. Most of us grew up with them and learned to ride as children. There are an estimated 1 billion bikes on the planet.
A good chunk of that billion seems to reside in my garage.
That’s kind of the joke about bikes, right? You always seem to collect old and busted ones, which end up clogging your storage space until they get donated, sold, or thrown out en masse. This is especially true about kids’ bikes, which are much cheaper and easier to replace than adult models, and consequently accumulate faster. It’s less money to buy a new sweatshop-made kid’s bike (like the one pictured in Figure 1-1) than it is to get that bike’s wheel repaired in a bike shop. Between the cost of labor and parts, why not just buy new? On the other end of the spectrum, there are the hipster cruisers often selling for upwards of $1,000 apiece. These are not bikes you would hesitate to fix.
Figure 1-1. This kiddie bike is crying out to be hacked!
There is a beautiful middle ground between buying cheap junk not worth repairing, and buying expensive hardware you can barely afford. The solution is to make and modify your own bicycle. This book shows you how, ranging from welding up a frame to converting your regular bike into a cargo bike capable of hauling a couple bags of groceries. Along the way, you’ll explore electronics, build a bike horn, add LED effects, and complete a bunch more projects to make your bike uniquely yours.
Bikes are everywhere. Find one and make it your own.
Origins
The bicycle was developed over time by many different inventors and mechanics across the world, with each person contributing a few new ideas to what became a very cool invention. The original two-wheeled, human-powered bike was the “Dandy Horse,” introduced in Mannheim in 1817 and Paris in 1818. It resembled a bike without pedals, chains, or gears, and it was propelled, Fred Flintstone-like, by the rider’s feet running along the ground. It took several false starts before bike makers settled on the now-classic configuration.
One of the most memorable was the iconic Penny Farthing bicycle shown in Figure 1-2, which flourished for barely a dozen years in the late 1870s and 1880s. While just a fad, the Penny Farthing became a symbol of the Victorian era, and its technology lives on: bike makers’ attempts to find the perfect wheel ratios led to the adoption of the chain drive as the go-to method of propulsion, and those ratios still exist today.
The creation of the chain drive, and its adoption by bicycle manufacturers, had in effect created a recognized standard bicycle: two wheels of identical size, with a metal frame connecting the wheels, and a sprocket equipped with pedals positioned between them. The cyclist sits on a saddle attached to the frame, and his or her pedaling energy is transmitted to the rear wheel with the help of a chain drive.
About the same time that this standard settled into place, around the end of the 19th century, a full-fledged bike craze began sweeping the world.
Figure 1-2. The Penny Farthing was a popular configuration of bicycle in the late 1800s
Anatomy of a Bicycle
Taking those configurations into consideration, a bicycle still boils down to a basic set of components: two wheels (usually), a frame to connect them, a place to sit, a braking system, and a set of pedals connected to an axle with a chain to drive the whole thing. Let’s now review the various parts of the classic bike.
Brakes
The things that slow your bike down. Most adult bikes use cable brakes like the set shown in Figure 1-3. Another type is the coaster brake, the classic feature of kids’ bikes. Well-heeled bike riders also dabble in disc brakes, which work by grabbing a disc mounted parallel to the wheel, rather than grabbing the wheel itself. Some cyclists remove the brakes altogether, preferring to rely on their biking skills to slow down in a hurry.
Figure 1-3. Stop your bike on command with a set of brakes
Brake Lever
You can control your brakes with these handlebar-mounted levers. Like the model shown in Figure 1-4, brake levers are usually constructed to be gracefully curved, in order to be comfortable to grip for long periods of time.
Figure 1-4. Squeeze the lever to slow down the bike
Cassette
When you hear about a bike having speeds, what this means is that it has multiple gears of different sizes. A big gear is slow, but has a lot of turning power to get you up hills. By contrast, a small gear is much faster, but doesn’t have the torque to do the same hill. The cassette is the stack of gears on your bike, like the ones seen in Figure 1-5.
Figure 1-5. The cassette is the stack of gears that the derailleur interacts with
Chain
Made of interlocking metal links, the bike’s chain (Figure 1-6) is a flexible way to transmit energy from the pedals to the wheels, and thereby move the bike. Because it’s made up of links, you can make it whatever length you want. This will prove very convenient when you start hacking frames!
Figure 1-6. A bike chain allows you to turn the rear wheel with the pedals
Chainring
A chainring is the big gear that pedals are mounted to, as shown in Figure 1-7. It is this gear that moves the chain, because the cassette is mounted to it. The one shown here has been customized with a stenciled paint job.
Figure 1-7. Chainrings turn the chain as you pedal
Derailleurs
These are the widgets that move the chain from one gear to the next, increasing and decreasing torque and speed (sort of like the transmission in a car). So-called “10-speeds” usually have front and back derailleurs, while bikes with fewer speeds might only have a single derailleur. And fixies do away with them altogether, forcing their riders to make do with a single speed. You can see a derailleur in Figure 1-8.
Figure 1-8. Derailleurs control the chains, allowing you to switch speeds while moving
Frame
The frame (Figure 1-9) is the chassis onto which all of the other parts of the bike are affixed. Typically it’s made of welded steel tubing, giving it strength but relative lightness. However, many other materials are possible, ranging from “retro” all-wood frames to ultralight carbon-fiber models. In Chapter 7, we’ll delve into frames big time, exploring the different parts of the frame and learning how to weld one of our own.
Figure 1-9. Your bike frame keeps the bike’s moving parts in order
Gear Shifts
These controllers interact with the derailleurs to switch gears, enabling you to adjust the gear ratios to allow you to have more or less torque, depending on the riding conditions. Sometimes gear shifts look like little levers, like the ones shown in Figure 1-10, while other types are knobs on the handles.
Handlebars
It turns out that holding on to your bike is super important, and because of this, you’ll find a wide variety of handlebar styles depending on what type of bike you’re looking at, as well as the preferences of its owner. Mountain bikes, like the one pictured in Figure 1-11, use straight handlebars.
Figure 1-10. Gear shifts control the derailleurs and allow you to move the chain from one gear to the next
Figure 1-11. You need something on the bike to hold on to—let’s make it as comfortable as possible!
Pedals
Every bike comes with pedals. Not surprisingly, there are a million different types of pedal and some are quite specialized. Racers favor racing cleats that prevent your shoes from slipping off the pedals, while others use radical friction, like the Odyssey pedals in Figure 1-12, to accomplish the same task.
Figure 1-12. These cool pedals may kill your shins, but your feet won’t slip off
Saddle
Also known as the bike’s seat, the saddle (Figure 1-13) is another part of the bike that is quickly switched out for a nicer upgrade or more customized configuration. Some seats are more padded, with gel packs making it more comfortable to sit for a long period of time. Racing saddles are made as light and aerodynamic as possible, at the price of not being as comfy.
Figure 1-13. A comfortable saddle, particularly one adorned with a unicorn, makes the bike experience more enjoyable
Tires
Tires (Figure 1-14) are a pain to maintain—you have to pump them up, and sometimes they rupture no matter how carefully you avoid debris in the street. That said, a good set can make the bike-riding experience much smoother and more comfortable, not to mention safer. In Chapter 6, you’ll have the opportunity to learn more about them.
Figure 1-14. Choose the right tires for your terrain
Variants
Back in the late 1800s and early 1900s, in those first few heady decades of hacking, bicycle builders tried out countless variations of the two-wheel-balancing-vehicle combination, before eventually settling on the configuration we’re accustomed to seeing. These days, bikes come in lots of different shapes and arrangements, taking advantage of the fact that we are all unique and have differing needs when it comes to a bike.
This book assumes you’ll be working on a bike with the standard configuration: two wheels of equal size (often around 26” in diameter), a saddle on which you sit, handlebars to steer the front wheel, and pedals connected to a gearing system to make it move. Most of the options in the bike store will have the same style. Chances are every bike you have in your garage follows this design. Don’t let that faze you! Check out these other types of bike that you’re likely to encounter.
BMX
These bikes feature smaller-than-average wheels, often with plastic spokes. They are named for Bicycle Motorcross (with the “X” standing in for “cross”) racing, where competitors jump their bikes and perform other stunts while racing around a dirt track. Because of this need for athleticism, BMX bikes also have a smaller frame size than standard bikes, looking like—or actually being—a kid’s bike. Despite this, many adults ride BMXes out of nostalgia or simply for the fun of it.
Folding
These bikes are intended to be transported compactly, and therefore their frames fold down. That, plus the smaller wheel size, make them easier to store in an apartment closet, for instance.
Just Hack It
Hacking is the opposite of that beautiful, gleaming $2,000 bike. Which is not to say its beauty isn’t really worth two grand—but I’d never want to hack it. Consider instead that old beater, like the one shown in Figure 1-15. It’s crying out for a new paint job, a cargo trailer, or possibly something even more exciting (maybe a way to generate electricity, a smartphone rig, or a sweet LED headlight?). With that junker, you get the freedom to play and hack without damaging something expensive.
Bike hacking is nothing more than modifying your bike to work better for you, fixing it when repairs are needed, and otherwise making it more your own. In a sense, it’s taking total ownership of your bicycle—as well you should, considering your safety and your transportation needs depend on it. It also enables you to fix it more readily. Once you’ve stripped down and reassembled a bicycle, chances are nothing about its repair will stymie you.
Figure 1-15. This old beater has better days ahead of it
More importantly, once you’ve fixed and modded a junker, you’ll be liberated to do pretty much anything with your bike. It can be something as simple as installing new reflectors, or as complex as building an Arduino-powered lighting system.
Just hack it.