What Parts Does the Road Bike Have?

Overview of the Bicycle Industry

Taiwan enjoys the reputation of being the kingdom of bicycle manufacturing. After 40 years of development, Taiwan has become the world's largest exporter of bicycles. In the past 10 years, under the low-price competition between China and India, domestic industry players have gradually transitioned into making mid-to-high-end, and higher-end bicycles. In terms of electrically assisted bicycles, it has increased production by 125% compared with 2018. Even during the 2020 COVID-19 pandemic, from January to October, there was a 20% growth rate compared to the same period in 2019. There are presently four major trends taking place in the development of the global bicycle industry, namely: going to lightweight, electrification, intelligence and networking, and sharing and services. With the bicycle industry booming, mastering key international technologies will give manufacturers the opportunity to meet the different demands in the market, and give added value to bicycles.

What parts does the bicycle have?

1. Frame
   The frame is the most important basic structure of a bicycle and is a decisive factor that affects the riding experience. Most frames are made in a rhombus shape, as it is the most stable structure and is the most economical to produce. When purchasing, you should pay attention to whether the size of the frame matches your height. A good frame will be light in weight and strong. Common materials frames are made of include aluminum alloy, titanium alloy, carbon fiber, and synthetic steel.
   • Head Tube: Connects the Top Tube and the Down Tube, the Front Fork passes through it, and the Headset is built into it.
   • Top Tube: The frame tube that connects the Head Tube and the Seat Tube.
   • Down Tub: The frame tube that connects the Head Tube and the Bottom Bracket.
   • Seat Tube: The length of the Seat Tube will directly affect the riding experience. Choose a suitable frame size based on the rider's height.
   • Seat Stay: Connects the upper edge of the Seat Tube to the Rear Axle.
   • Chain Stay: Connects the Down Tube to the Rear Axle.
   • Fork: Controls the front wheel and provides cushioning and shock absorption. Road bikes usually adopt more rigid front forks, with a bit of an arc at the fork end to produces an offset. Mountain bikes are equipped with flexible, shock absorber front forks, to cope with more forceful vibrations on harsh roads. This also helps the front tire to maintain contact with the road for better control. There are two types of suspension forks: connecting rod and crumple type. Most mountain bikes usually use crumple type, while connecting rod type suspensions are mostly used in bikes with smaller diameter frame tubes.
   • Saddle: Supports the weight of the rider. When selecting, comfort should be the main consideration to reduce pressure and friction. The cushion structure is divided into the cushion shell, cushion underframe (seat bow), reinforcement sheet, cushion, and surface layer. The cushion supports most of the body's weight and is most likely to cause pressure and friction. Different models of vehicles need to use different forms of cushions. 
   • Mountain bikes have easy to sit on saddles which can reduce fatigue. The road bike must reduce frictional resistance as much as possible, so the appearance is relatively slender. The saddle cushion should have support points and comfort for long-distance riding. In addition, for women with a wider pelvic cavity, the rear part of the cushion is designed to be wider and can reduce the feeling of pressure. It can be selected according to the indicated purpose of the cushion.
   • Seat Post: Connects the seat cushion and the frame to support the weight from the seat cushion.
   • Seat Post Clamp: Clamps the seat tube and the frame for easy adjustment of the height of the seat tube.
2. Steering system
   A headset inside the head tube provides bicycle travel control.
   • Handlebar: Is connected by the stem to the front fork to control the driving direction. Generally, road bikes use curved handlebars to lower the upper body to reduce wind resistance. There are also flat-handled road bikes. Handle bears need to be able to bear impact and pressure from the body's weight. During acceleration and climbing there will bear the force of pull on the handlebars. The requirements for rigidity and fatigue resistance are self-explanatory. The handlebars come in many shapes depending on the function of the bike type. Road bikes often use down-bending handles. Mountain bikes are equipped with straight handles.
   • Handle Tape: Non-slip, shock-absorbing tape can will give a good grip and prevent sweat from corroding handlebar.
   • Brake/ Shift Lever: The brake lever and shift lever of road bikes are usually integrated into one piece which is installed on the handlebar.
   • Head Sets: Bearing bike parts installed on the upper and lower ends of the head tube to hold the front fork steering tube and allow it to steer.
   • Stem Cap: Protective bike parts, used as a dust-proof and waterproof outer cover for the stem. The Stem connects the handlebar and the front fork steering tube. It controls the driving direction, and maintains balance.
3. Braking system
   Controls the slowing and stopping of the front and rear wheels.
   • Caliper Brake: Movable bike parts that hold the brake blocks which slow down or stop the wheels. C-type brake clamps (C clamps for short) are commonly used on road bikes, but disc brakes are also used.
   • Brake Block: Makes contact with the wheel frame and clamps to the frame to restrain the wheel from rotating, thereby decelerating or stopping the bike.
   • Brake Cable: Connect the brake control on the handle bar to the caliper brake.
4. Gear transmission system
   The variable speed gear system is like the heart of a bicycle, transferring the force that drives the bicycle forward. These components bear constant force, and because they are close to the ground, they are susceptible to corrosion caused by dirt or contaminants. Therefore, regular maintenance and inspection are very important.
   • Pedals: Feet are directly applied to the pedals to push the bicycle. There are various tuprs pf petals, including pedals that clamp onto the rider’s shoes.
   • Crank: A lever that connects the bottom bracket to the pedal, and transmits the pedaling force to the chain.
   • Large plate Chainring/ Chainwheel: A large gear set connected to the right crank that the chain attaches to.
   • Bottom Bracket: A combination of bike parts that connect the big plate, the crank, and the frame.
   • Chain: Connects the chainring and the freewheel gear set to transfers energy to the rear wheel.
   • Freewheel/ Cassette: A combination of multiple gears, placed on the ratchet seat of the rear wheel.
   • Front Derailleur: Controls the switching of the chain between various gears on the front chainring.
   • Rear Derailleur: Controls the switching of the chain between various gears on the freewheel gears.
   • Derailleur Cable: Connects the shift lever on the handlebars with the derailleur.
5. The wheel
   The bicycles move forward or stops depending on friction between the tires and the ground. Therefore, the material and design of the wheels will affect the speed and stability of riding. The wheels include a hub, spokes, and rims. The hubs should minimize internal frictional resistance and withstand strong torque during pedaling. The spokes should be rigid enough to firmly connect the hub and the rim. Flat spokes can also reduce the warping and reduce wind resistance. The rim structure must allow it to withstand radial impact and maintain a constant round shape with minimal deflection. Wheelsets should be lightweight, have good rigidity, and provide smooth hub rotation.
   • Rim: The outer frame of the wheel. The tire is fixed on the rim.
   • Hub: The bearing that drives the rotation of the rim. The rear hub works in conjunction with a corresponding freewheel set.
   • Spoke: The wire which connects the hub and the rim.
   • Nipple: A nut that fixes the spokes to the rim.
   • Cassette Body: Inside has a one-way ratchet, which engages the freewheel to drive the rear wheel of the bike forward when force is placed on the pedal, and idle freely when the pedal is not being rotated.
   • Quick Release: Allows the bike parts of the fixed wheelset to be quickly removed or replaced by opening or closing the handle.
   • Dropout: The small groove at the end of the front fork and the rear triangle of the frame that the wheelset can fit into.
   • Tire: According to different needs, there are various specifications and tread patterns to choose from. The thinner the tire, the lower the rolling resistance; the wider the tire, the better the shock absorption. Road tires are generally divided into tube tires and tubeless tires and wheelsets. The driving and stopping of the bike mainly relys on the friction between the tires and the ground. The tire tread affects the contact area with the ground, which affects the friction and tracking of the bike. Mountain bikes need to use large tires to increase cushioning and traction on rough road. Road bikes use narrow tires with higher tire pressures to reduce friction.
   • Valve: The tube where tires are inflated from. The two commonly used valves are American and French. American air nozzles are the same as automobile and locomotive tires, and can be inflated in general car shops and gas stations. French air nozzles require additional adapters.