Analysis of hub structure of carbon fiber road wheelsets

When choosing a road wheelset, in addition to the material, rigidity, and weight of the carbon fiber rim, the design and structure of the hub are also important factors that determine performance. The structure of the hub directly affects the smoothness of riding, transmission efficiency, maintenance difficulty, and the overall riding experience. Today, we will take a deep look at the different hub structures commonly found in carbon fiber road wheel sets and analyze their advantages and disadvantages. You are also welcome to point out some of the hub structures that are not mentioned in the comments section!

1. Traditional hub structure (J-bend)
The traditional J-bend hub is the most common type of hub at present. It uses a "J"-shaped spoke angle, with the spokes bent on the outside of the hub. This design is generally considered to be the simplest and easiest repair option.

Advantages:
(1) Low cost: Due to its mature manufacturing process, J-bend hubs are generally relatively cheap.
(2) Easy to repair: The installation and replacement of spokes are relatively simple, and they can be adjusted using standard tools.
(3) Wide applicability: This design is suitable for almost all types of road bikes, including high-end and entry-level models.

Disadvantages:
(1) Heavier weight: J-bend hubs are usually slightly heavier than other types of hubs, although this difference may not be obvious in high-end carbon fiber wheels.
(2) Larger spoke angle: Larger spoke angles may result in slightly lower transmission efficiency, especially during high-intensity riding.

2. Straight-pull hub

Straight-pull hubs use a straight-pull spoke installation method, that is, the spokes are inserted directly from the outer edge of the hub to avoid bending. This design is becoming more and more popular in high-end road bikes and racing wheels.

Advantages:
(1) Uniform spoke tension: Since the spokes do not bend, the spoke tension distribution is more uniform, which can provide higher rigidity.
(2) Higher transmission efficiency: The straight-pull spoke design reduces unnecessary angle loss, making the transmission efficiency relatively high.
(3) Lighter: Since there is no bent part, the weight of the straight-pull hub is usually lighter than the J-bend design.
(4) Reduced risk of spoke breakage: Straight-pull spokes reduce bending stress, thereby reducing the possibility of spoke breakage.

Disadvantages:
(1) Difficult to repair: Straight spoke hubs require special tools to replace or adjust spokes, and repair and adjustment are more complicated for non-professionals.
(2) High price: Due to higher manufacturing process requirements, straight-spoke hubs are usually more expensive than traditional J-bend hubs.

3. Carbon Hub
With the development of carbon fiber technology, some high-end road wheel sets have begun to use carbon fiber materials to manufacture hubs. The main advantages of carbon fiber hubs are lightweight and improved rigidity.

Advantages:
(1) Ultra-light design: Carbon fiber hubs are lighter than aluminum alloy hubs, which can significantly reduce the total weight of the wheelset and improve acceleration performance.
(2) Rigidity and responsiveness: Carbon fiber has high rigidity, which can improve the overall rigidity of the wheelset, especially suitable for high-speed driving.
(3) Beautiful: Carbon fiber hubs have a unique appearance, which meets the pursuit of individuality and aesthetics by high-end fans.

Disadvantages:
(1) Brittleness: Compared with metal materials such as aluminum alloy, carbon fiber is more brittle and easily damaged under extreme impact.
(2) Expensive: Carbon fiber materials and processing technology are relatively complex, resulting in the high price of this type of hub.
(3) High maintenance requirements: Although carbon fiber hubs have a long service life, once damaged, repair is relatively complex and expensive.

4. Hub with internal gearing

An internal hub is a relatively rare hub structure, usually used in wheels with internal gearing systems. It changes gears inside the hub through an internal gear system, rather than relying on an external flywheel and derailleur.

Advantages:
(1) Reduced external wear: Since the components of the gearing system are completely encapsulated in the hub, the impact of the external environment on the gearing system is reduced.
(2) Low maintenance: Internal hub designs are usually less maintenance-intensive, especially in extreme weather conditions, as they can avoid the effects of dirt, moisture, etc.
(3) High efficiency and stability: Internal gearing systems provide a smooth and stable gearing experience and are not easily affected by chain jumping or gear shifting delays.

Disadvantages:
(1) Heavier weight: Internal gearing systems are heavier than traditional wheels with external gearing systems.
(2) Higher cost: Internal hubs are complex in design and usually require more precision processing, so they are more expensive.
(3) Poor adaptability: Internal gearing systems are not as universal as external gearing systems and are suitable for frames and wheels that require specific configurations.

5. Bearing-less Hub
This design is relatively rare, and some manufacturers are exploring ways to reduce the weight of the hub by reducing the number of bearings, thereby improving overall performance. This type of hub design uses an innovative sliding mechanism instead of traditional bearings.

Advantages:
(1) Lightweight: By reducing the number of bearings, the weight of the hub is significantly reduced, which is suitable for riders who pursue extreme lightness.
(2) Innovative design: Not relying on traditional bearings, it can avoid bearing wear problems.

Disadvantages:
(1) Poor durability: Due to the lack of traditional bearing support, this type of hub may experience friction or wear after long-term use, affecting durability.
(2) Limited adaptability: Currently, the adaptability range of this type of hub is relatively narrow and is rarely used in the market.

Conclusion:
Choosing the right hub structure depends on riding needs and budget. If you value lightness and efficient transmission more, a straight-spoke hub may be the best choice. If you prefer a cost-effective and easy-to-maintain option, a traditional J-bend hub will be a good choice. For high-end racing and competitive cyclists, carbon hubs and internal hubs offer more professional performance.
No matter which hub structure you choose, understanding their pros and cons and making a decision based on your needs will help you better improve your riding experience and enjoy every road you set foot on.

 

Tags: #J-bend hub #Straight-pull hub #Carbon Fiber hub #Hub with internal gearing #Bearing-less Hub #Hub #Spoke #Spoke tension #Spoke breakage #Aluminum hub #Speed ​​system #Derailleur #Bearings