Aerodynamics Part 2: Clothing and Equipment

Aerodynamics Part 2:  Clothing and Equipment

We recently published a blog post around one of the latest hot topics in the Cycling World - the recent decision by the UCI to outlaw some riding techniques that they deemed to be unsafe.  

Included in the post was information from leading aerodynamic experts Len Brownlie and Nathan Barry, based around the actual real-world advantages of aero techniques in road cycling - and if it's all what its cracked up to be.

If you missed the post, you can read it here.

Below, we've expanded on the interview to include further details and information around kit, clothing and equipment - and how much these can affect aerodynamics and performance in road cycling.

Part 2:  What to Know About Aero Gear

As you will have seen in Part 1:  When every watt counts, good aerodynamics can equal easy speed and energy savings. Your kit can go a long way for reducing drag, so you can go further and faster with less effort.

Here’s a look at what matters most...


A rider wearing state-of-the-art apparel can buy more than two minutes over a 40K TT - compared to a counterpart wearing an ill-fitting club kit flapping in the breeze.

Len Brownlie, Ph.D. is an aerosports expert who has previously worked with Nike to develop vortex generators (which are kind of like a series of tiny wings) for their competitive athletic wear.

"The technology is only improving as engineers turn to clothing as a hot frontier for major drag reduction".

"For example, for track-running sprinters, they can reduce drag by about 10 percent, which equals a one percent improvement in performance over 100 meters - this is the difference between winning and not...  That is over only 100 metres - imagine that over 100 or 200 kilometres..."

"Avenir Cycling is amongst the leading apparel manufacturers who have developed similar concepts for time trial suits, placing vortex generator-like textured fabrics on the shoulders, upper arms down to the elbows, and on the thighs, which should help ‘roughen’ up the air as it flows over your limbs and keep it closer to the body to create less drag.”

Another example of this was demonstrated by Castelli back in 2017, when they unveiled the Team Sky Vortex skinsuit at the Tour de France.  Ultimately, the suit was outlawed by the UCI, however our designers have been endlessly testing to bring a compliant alternative to the peloton.

Froome Castelli Skin Suit

Interestingly, there’s a definite point of diminishing returns, however, Brownlie notes:

“Our recent wind tunnel tests of time trial suits have revealed that some of these other suit designs may have gone overboard with too many textured panels,” he says. “The lowest drag suits we have tested confine the textures to the shoulders and upper arms and rely upon seam designs that are aligned with the airflow and fabrics that are very smooth and tight fitting"


Your bike accounts for up to 30 percent of your total drag, which is significant, especially for riders who don’t have aerodynamic postures on the bike:

“If you’re not particularly flexible or aren’t built in a way that lets you assume an aerodynamic position for very long, having a bike that reduces drag can help make up for that,” he says. “No matter what you’re doing, the bike is always working for you.”

For the bike itself, even on bikes that are mighty fast to begin with, tube shaping can shave significant amounts of time.

For example, when our engineers tested the SystemSix, the brand's first and radically designed aero road bike, against its Evo race bike, they found a rider could save over two minutes over the course of a 40K time trial (assuming both bikes used the same wheels).

That savings jumps closer to three minutes if you compare the aero bike to the traditional race bike with low profile wheels. 

The right cockpit design has a big influence, Barry says. “An aero handlebar is really, really important for reducing drag.”


Another hot topic this week is Chris Froome's take on Disc brakes, saying he isn't really a fan of the new tech.  Interestingly, disc brakes offer more than just improved ability to slow or stop; they also allow for a more aerodynamic frame construction:

Nathan Barry:

“If you can take the rim brake off the front of the bike, there’s a lot of freedom of design. You’re going to see a lot of improvement in drag reduction there.”


Wearing a classic aero TT helmet rather than a standard road lid can save you more than a minute over a 40K course, assuming a speed of roughly 50 kph, according to Brownlie’s research. 

But TT helmets are notoriously uncomfortable and restrictive. Fortunately, today’s aero road helmets are better and more comfortable than ever.

“Modern aero road helmets such as the Giro Vanquish and the Specialized S-Works Evade II are very close in terms of aerodynamics to the traditional full aero lid, but they’re more comfortable and don’t turn into a sail if you look down,”

Brownlie says. “If you’re going to pick just one helmet for all around performance, I would pick one of those.”


"Wheels are complicated because they’re paired with tires, which can dramatically change drag", Brownlie says.

“Several years ago, we tested the same aero front wheel with tires manufactured by five different manufacturers. We were astounded to learn that wheel drag could vary by up to nine percent depending upon tire selection.”

But generally speaking, you’ll get the greatest reduction in drag from a fairly deep 60mm to 90mm rim, Brownlie says.

The time savings for good aero wheels are significant, according to our in-depth research and testing.

"Even on an aero road bike, the addition of aero wheels saved 48 seconds over a 40K TT at 300 watts compared to a typical 30mm-depth alloy training wheelset".

Avenir aerodynamic philosophy

So, how do we approach aerodynamics at Avenir...?

As a performance cycling brand, aero-efficiency is something we put at the forefront of our design and production process.

Avenir Cycling Director of Performance, Phil Smith:

"The key takeaways from these studies is the concept of incremental improvements across all aspects and sectors of your kit, equipment, training and posture, even if they seem somewhat marginal - will in reality add up to a significant, collective overall improvement in speed, efficiency and performance." 

"All Avenir Cycling kit and equipment is meticulously designed and engineered in line with the core principles of aero performance for our riders and racers.  But we've proved Aero doesn't have to be uncomfortable, and aero doesn't have to be super-expensive".

"We strive to clothe our riders in kit that can balance all the aspects - fit, form, comfort, technical and aerodynamic efficiency - remaining highly-durable - and maintaining our price-point".

"Our riders ultimately benefit from a huge amount of background technology and research - that we can bring to the road for a whole lot less than some of our competitor brands - and that's with no compromise on quality whatsoever"

"This is really what our core brand-concept is built on - and one we are really proud of".


Avenir Cycling specialises in the design and production of high-performance technical Road & Track cycling apparel.

Psst...  Fancy a discount off our Elite Aero Race Kit...?  Make sure you sign up below for more news, updates, and exclusive access to Avenir Squad member deals ↓