Hooked vs Hookless: Differences Between Old and New Rim Designs and How to Choose

In recent years, one of the most controversial topics in the cycling wheel industry has been the Hookless rim design. Brands such as Zipp, ENVE, and Roval have all launched Hookless carbon rims, claiming they are lighter, stronger, and more aerodynamic. But opponents worry about safety issues and tire compatibility. Is Hookless progress or regression? Let’s take an objective look.

What Are Hooked and Hookless Rims?

Hooked Rims (Hooked / Crochet)

The traditional rim design features an inward-curving “hook” at the rim edge, and the tire bead locks inside this hook. This design originated with aluminum rims in the 1970s and remains in use today.

Hookless Rims (Hookless / Straight Side)

There is no hook at the rim edge—instead, there is a flat, straight sidewall. The tire bead is held in place against the rim wall by air pressure. This design comes from automotive wheels—nearly all car wheels use a Hookless design.

Advantages of Hookless

1. Manufacturing Advantages

Aspect	Hooked	Hookless
Carbon layup	Complex (requires precise molding at the hook)	Simple (straight sidewall)
Mold design	Complex	Simple
Yield rate	Lower	Higher
Rim edge strength	The hook area tends to become a stress concentration point	More even stress distribution

The Hookless design makes carbon rim manufacturing easier with higher yield rates. The absence of a hook at the rim edge means the carbon fabric does not need to be precisely molded around sharp turns, reducing the risk of manufacturing defects.

2. Weight Advantage

The hook requires additional carbon layers to ensure strength. Removing the hook can save 10-30g of rim weight. This difference may seem small, but it matters in top-tier wheelsets pursuing extreme lightness.

3. Tire Mounting Uniformity

Tire mounting is more uniform on Hookless rims. On hooked rims, the tire bead needs to be worked over the hook to seat properly, which can sometimes result in localized unevenness. The straight sidewall of a Hookless rim allows the bead to seat more naturally.

4. Tubeless Sealing

When paired with Tubeless tires, the contact area between the bead and rim wall on a Hookless rim is larger and more uniform, theoretically providing better sealing.

The Controversies and Risks of Hookless

1. Tire Compatibility Issues

This is the biggest point of controversy with Hookless. Not all tires support Hookless rims—using an incompatible tire could lead to a high-speed blowout.

Tire Brand	Hookless Support
Continental GP5000 S TR	Supported
Vittoria Corsa Pro	Supported
Pirelli P Zero Race TLR	Supported
Michelin Power Cup TLR	Partially supported
Schwalbe Pro One	Supported
Non-Tubeless Ready tires	Not supported

Key point: Hookless rims can only be used with Tubeless Ready tires explicitly marked as compatible. Traditional non-Tubeless clincher tires and tubular tires cannot be used on Hookless rims.

2. Tire Pressure Limits

Most Hookless rims have a maximum tire pressure limit, typically 5-6 bar (about 72-87 psi). For riders using 23c or 25c tires, this pressure may be on the low side. However, with the trend toward wider tires, 28c and above at 5-6 bar is already sufficient.

3. Safety Concerns

The most serious safety concern is: what happens if a tire comes off a Hookless rim at high speed? On a hooked rim, the hook provides a physical barrier preventing the tire from coming off. A Hookless rim has no such barrier, relying entirely on air pressure and the bead fit.

However, proponents point out:

• Automotive wheels are also Hookless, with a good safety record
• With correctly matched compatible tires and pressure, the risk of tire detachment is extremely low
• ETRTO standards have already established safety specifications for Hookless

Current Market Trends

Brands That Have Fully Transitioned to Hookless

• Zipp (full range Hookless)
• ENVE (latest series Hookless)
• Roval (new models Hookless)
• Giant/CADEX (new models Hookless)

Brands Still Offering Hooked Options

• Shimano (full range still Hooked)
• Campagnolo (still Hooked)
• DT Swiss (some models offer a choice)
• Mavic (still Hooked)

ETRTO Standards

The European Tyre and Rim Technical Organisation (ETRTO) has published compatibility standards for Hookless rims and tires. As long as both the rim and tire comply with the latest ETRTO standards, using them together is safe.

Considerations for Taiwanese Riders

Reasons to Support Hookless

1. Stronger rim surface (no stress concentration)
2. Lighter weight
3. Future trend
4. Better Tubeless sealing

Reasons Against Hookless

1. Limited tire choices
2. Cannot use traditional clincher tires
3. Tire pressure limits
4. Requires extra attention to tire compatibility
5. Some popular tires in Taiwan may not be compatible

Practical Recommendations

1. If you primarily use Tubeless tires: Hookless is fine
2. If you still use traditional clincher tires: Choosing a Hooked rim is safer
3. If you frequently switch tire brands: Hooked rims offer broader compatibility
4. If you choose a Hookless rim: Strictly follow the tire compatibility list and pressure limits

The Future of Hooked and Hookless Coexistence

Currently, hooked and Hookless rims coexist on the market. This situation may continue for some time until:

1. ETRTO standards become more mature
2. All mainstream tire brands support Hookless
3. Consumer confidence in Hookless safety is established

Shimano still insists on the Hooked design, and their reasoning is to protect consumers from danger caused by using incompatible tires. This conservative but responsible attitude deserves respect.

Summary

Hookless is not a gimmick—it has real engineering advantages. But at present, it is not yet the right choice for everyone. If you are willing to strictly follow tire compatibility requirements, use a Tubeless setup, and stay within recommended pressure limits, Hookless rims are a safe and advanced choice. If you prefer the freedom to swap tires at will, favor higher tire pressures, or take a cautious approach to new technology, Hooked rims remain a solid choice.

Related Reading

• A Complete Analysis of Hookless Rim Technology: Revolution or Compromise?
• Rim Tape Selection and Installation Tips for Tubeless Carbon Wheels
• Road Bike Wheelset Buying Guide: Daily and Racing Trade-offs Between Aluminum and Carbon Rims
• The Complete Road Bike Wheelset Guide: A Comprehensive Comparison of Aluminum, Carbon, Tubular, and Tubeless