Horses for Courses
The bewildering array of bikes is due not only to marketing, but because no one type of bike is ideal for all uses. The above equine saying is often invoked by bike enthusiasts (James included) to justify owning multiple bikes for varied purposes. Through my cycling career, at any one time, I have had one bike which was my recreational vehicle and one for commuting to work. If I had to live with just one bike, it would be my commuting bike, no regrets. Why such devotion? Simplicity = Joy.
The American bicycle industry promotes and offers bicycles ideally suited for recreational and sport use. They are designed for high speed on open roads or off-road trails in a recreational setting. Furthermore, the modern bicycle industry thrives on fads and divergent systems for this narrow range of use, that marginally enhance performance at increased complexity and cost.
Performance is not limited to what the wind tunnel or rolling resistance drum tells us, however, in the real world performance includes reliability, all-day comfort, serviceability and affordability. Fifty years of cycling and wrenching have convinced me that simpler and time-tested mechanisms are not only less expensive. In most over time, they outperform more complicated ones. The two greatest performance/reliability tradeoffs are tires and the bicycle's drivetrain.
A necessary complication for human-powered travel is multiple gears. Because the human engine is limited to about a quarter horsepower, it needs help from gearing to convert that power into forward motion on a bicycle over varied terrain.
The gearing most universally available for bicycles is the derailleur system, where a mechanism on the right side of the bicycle moves the drive chain ("de-rails" it) between sprockets with different numbers of teeth. The rear derailleur shifts the chain over from 5 to 12 sprockets on the rear wheel, and the front derailleur moves the chain among 2 or 3 sprockets attached to the pedal crankarms. In addition, the rear derailleur runs the chain through a spring-loaded arm to maintain tension over the different amount of chain wrap on the different sized sprockets.
The derailleur system offers the most gears and widest range for the lowest weight. The derailleur seems simple to understand and maintain because, well, there it is in plain sight where you can access it. Nonetheless, it is definitely an enthusiast's mechanism requiring pampering to work properly. Hanging out there on the bicycle frame, derailleurs are exposed to dirt, road grit, the elements, and damage, and they require frequent cleaning and tuning.
The derailleur system is the only chain drive in all of mechanics where the chain is deliberately run out of line, with the rear derailleur responsible for forcing the chain into alignment with one of the sprockets on the rear wheel. to function. With such a gargantuan task, and exposed to all the grit, it is not surprising that derailleurs wear out quickly.
The experience of riding a derailleur bike has its annoyances as well, since the chain and therefore the rear wheel must be turning to have the chain derailed from one sprocket to another. Not so simple in stop-and-go traffic.
My commuting/errand/casual bike eschewed derailleurs and ranged from fixed to five internal gears. Please consider the non-derailleur options for simplicity, reliability and durability. Check the subpages on "Fixed Gears" and "Internal Gear Hubs" to read about the virtues of the two non-derailleur gear systems we offer.
Derailleur-Equpped Bikes offer the most gears with a front derailleur shifting over 2 or 3 gears and a rear derailleur selecting among N = 8, 9, 10, 11, or 12 gears for total combination of 3 X N. This makes them the most versatile genre, with lots of gears for any terrain.
Internal Geared Bikes use, internal gear rrear hubs, with fully enclosed 2-8 speeds.They offer convenience and reliability to transport you and your gear day after day, through all kinds of weather.
Fixed-gear and single-speed bikes are the most simple and mechanically efficient bicycles, delightful if that one gear is the right for the terrain.