Choosing road bike wheels is one of the most crucial factors in determining the overall performance of the bike.

It's often said that wheels can make a bigger difference to ride feel than the frame itself. Riders with a strong interest in hill climbing, long-distance rides, or racing often find themselves grappling with the balance of "lightness," "cruising performance," "crosswind stability," and "stiffness."

Amidst this, ICAN's latest carbon wheel, the "AERO 40 II," has been steadily gaining attention on social media, YouTube, and among some hill climbing communities.

The specs alone are astounding.

・40mm depth
・23mm internal width wide rim
・Tubeless compatible
・Sapim CX-Ray spokes
・45T star ratchet hub
And then——

An incredibly light measured weight of 1177g.

Typically, wheels in this weight range often come with drawbacks such as:
"Ultra-light but susceptible to crosswinds"
"Lacking stiffness"
"Poor cruising speed retention"

However, the AERO 40 II significantly defies these conventions.

This time, we'll thoroughly explore its actual specifications, design philosophy, and "why this wheel is being chosen now."

First, the astonishing weight of "1177g"

Any road cyclist will understand how unusual this number is.

1177g for 40mm depth carbon disc brake wheels.

What's important is that this isn't just a catalog spec; it achieves this weight while incorporating a modern wide-rim design.

There are two main types of lightweight wheels.

One is the traditional narrow rim, low-stiffness type.
The other is the type that achieves both lightness and stiffness through modern design.

The AERO 40 II is entirely the latter.

In fact, the new carbon layup combining Toray T700/T800/T1000 reduces unnecessary weight while maintaining essential stiffness, rather than just simply thinning out material.

That's why,
The response at the moment of pedaling is exceptionally light.

There's less "sluggishness" when standing, and the acceleration with each pedal stroke on climbs is very sharp.

Riders participating in hill climbing events will particularly notice this difference.

Especially on gradients of 10% or more,
The "difference in wheel weight" directly translates to a difference in leg fatigue.

The feeling that riders who first switch to lightweight wheels often describe,

"My legs feel fresh."

The AERO 40 II is a wheel that allows you to experience that sensation quite distinctly.

However, the true greatness of this wheel isn't its "lightness."

Actually, the reason the AERO 40 II is so highly regarded isn't just its weight.

What's truly noteworthy, in fact, is the point that,

"Despite being 40mm deep, it's easy to handle."

Generally, with 40-50mm deep rims, the impact of crosswinds starts to increase.

Especially for lighter riders or those riding mountain descents, crosswind instability can be quite stressful.

However, the AERO 40 II employs a U/V hybrid shape.

This is a design philosophy increasingly adopted in recent high-end wheels, offering advantages such as:

・Smooth airflow
・Suppression of turbulence
・Reduced sudden handlebar snatching in crosswinds

In reality, recent "fast wheels" don't simply pursue aerodynamics in isolation.

What's important is "stable aerodynamic performance."

Wheels that feel scary in crosswinds ultimately cause riders to unconsciously slow down.

In other words, being fast only in theory is meaningless.

The AERO 40 II demonstrates excellent balance in this regard.

Handling feels natural even at high cruising speeds, and there's less fatigue over long rides.

Especially in environments like Japan, with frequent crosswinds and inconsistent road conditions, this ease of handling becomes a significant advantage.

Why is "23mm internal width" important?

Over the past few years, one of the most significant advancements in the road wheel industry has been internal rim width.

Older road wheels typically had internal widths of around 15-17mm.

However, current high-end models are increasingly standardizing at 21-25mm.

The AERO 40 II has a 23mm internal width.

This is a very modern design.

So, what changes?

The biggest benefit is maximizing tire performance.

It pairs exceptionally well with 28C-32C tires, offering advantages such as:

・Improved grip
・Reduced rolling resistance
・Enhanced ride comfort
・Improved cornering stability

These benefits are particularly significant for long rides.

In the current road bike world,
The era of "narrow tires = fast" is coming to an end.

Instead, the prevailing idea is that wider tires at appropriate pressures are faster and more comfortable in real-world riding.

The AERO 40 II is fully aligned with this latest trend.

The D91 hub is surprisingly good

Honestly, this was quite unexpected.

The ICAN D91 hub uses a 45T star ratchet.

45T means a very fast response time to pedaling input.

Especially in hill climbs or situations with frequent stop-and-go, this responsiveness feels incredibly satisfying.

Furthermore, it weighs only 280g.

Quite light.

Although hub weight is at the center of the rotating mass, it definitely impacts acceleration feel.

Moreover, with S&S steel bearings, rotational performance is smooth.

It lacks the "spins but questionable durability" feeling often found in inexpensive lightweight hubs.

Of course, a DT SWISS 240 EXP option is also available.

If brand reliability is a higher priority, choosing the DT version would be a good option.

However, in terms of cost performance, the D91 version is remarkably well-made.

The use of Sapim CX-Ray speaks volumes about its seriousness.

Anyone who knows wheels can gauge their "seriousness" by looking at the spokes.

The AERO 40 II uses Sapim CX-Ray spokes.

These are a super standard spoke used in high-end wheels worldwide.

The reasons are simple:

Light, strong, flexible.

And highly durable.

By using these spokes,

・Response during acceleration
・Stability while cruising
・Ride comfort
・Tension retention

All these aspects are brought together at a high level.

In other words, it's not just a "lightweight wheel," but a highly refined wheel built to last.

So, what kind of rider is it actually suited for?

The AERO 40 II is quite versatile.

We particularly recommend it to the following types:

Hill climbing enthusiasts

Undoubtedly a great match.

Its lightness is a major asset.

And with a 40mm depth, you won't get left behind on flats.

"I want to climb mountains, but I also want good cruising performance."

For such riders, it's quite ideal.

Long-distance riders

The comfort provided by the 23mm internal width + tubeless compatibility is significant.

It makes a huge difference in fatigue.

The fact that it's a lightweight wheel yet not overly delicate is also appealing.

First-time buyers of high-end carbon wheels

Actually, highly recommended.

The reason is its ease of handling.

For beginners, some of the latest ultra-deep wheels can feel intimidating in crosswinds.

However, the AERO 40 II offers high stability and fewer quirks.

Yet, it still allows you to truly experience "speed."

Honestly, the price is incredibly competitive.

Recently, the prices of wheels from well-known brands have become truly high.

Prices exceeding 400,000 to 500,000 yen have become common.

Of course, there's brand value.

However, purely looking at the specs,
The cost performance of the AERO 40 II is quite exceptional.

1177g
40mm depth
23mm wide rim
Sapim CX-Ray
Star ratchet
Tubeless compatible

All this content at this price point.

And if shipped from a Japanese warehouse, delivery is fast.

Honestly, I think this wheel will appeal most to those who are tired of paying for "brand logos."

Summary | A complete package that's "more than just light"

The ICAN AERO 40 II is not just a lightweight wheel.

・Light
・Fast
・Stable
・Comfortable
・Easy to handle

Its overall balance is exceptionally good.

In today's road bike market,
"Overall performance" is valued more than "niche performance."

In that sense, the AERO 40 II aligns perfectly with current road bike trends.

Especially for riders who want:

"To climb hills"
"To have good cruising performance"
"To be comfortable on long rides"
"But don't want to compromise on lightness"

This wheel will likely be a very attractive option.

Once you experience the acceleration of lightweight wheels, there's no going back.

And the AERO 40 II is a wheel that delivers that "initial thrill" quite powerfully.