Castelli Free Aero Race Bib Shorts Review

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If you look through Castelli’s range of bib shorts, you’ll notice that the Castelli Free Aero Race bib shorts are right up there among the best.

In fact, it’s third in line after the more luxurious Mondial and Premio bib shorts.

Popularity wise, the Free Aero Race bib shorts win hands down.

It strikes the perfect balance between quality, performance, and price. It’s the preferred choice of Castelli bibs for many cyclists, myself included.

The Castelli Free Aero Race bib short was first released in 2007.

Since then, Castelli has continuously worked to improve its subsequent versions after getting feedback from the professional peloton and recreational cyclists like you and me.

Major improvements are made in all departments, from the fabrics to construction methods, seat pads, waistband, shoulder straps, and grippers to improve the quality and more importantly, comfort


  • Most popular Castelli bibs. Strikes the perfect balance between quality, performance, and price.
  • Lightweight and breathable fabrics. Suitable for long and hot days in the saddle.


  • Sizing. Size can come up smaller.

Rosso Corsa - The Best of Castelli's Offerings

Castelli Free Aero Race Bib Shorts Rosso Corsa

One of the first things you’ll notice about the Castelli Free Aero Race bib shorts is the word Rosso Corsa printed at the back together with 2 Castelli logos just above the grippers at the front.

Rosso Corsa is a word used by Castelli to describe its premium offerings. Rosso Corsa products incorporate the best technologies Castelli has available to the consumer.

They can be found not only in bib shorts but everything else from jerseys to jackets, base layers, gloves, and even socks.

Forza and Vortex Dimpled Fabrics

Castelli Free Aero Race Bib Shorts Vortex Dimpled Fabrics

Made from lightweight and breathable fabrics, the Castelli Free Aero Race bib shorts weighs a measly 178g for a Medium size.

It’s perfect for those long and hot days in the saddle especially during the summer.

Compared to previous iterations, the fabrics are now softer and more stretchy to provide a snug, race fit. The inner layers uses a fabric called Forza that feels like a second skin and doesn’t crumple after washing. The outer layers uses a Vortex dimpled as a result from Castelli’s wind tunnel testing.

Castelli claimed it saves 10 watts when riding at 50km/h, but the only time I’m riding anywhere near that speed is probably during the descend. So, that doesn’t really matter, at least for me. It does look good though.

Remember the drama surrounding Team Sky wearing a vortex generator skinsuit en route to putting 4 of their riders in the top 10 on the 1st stage of the 2017 Tour de France?

Geraint Thomas won the stage and wore yellow the next day.

Same fabrics.

Progetto X2 Air Chamois

Castelli Free Aero Race Bib Shorts Progetto X2

The Castelli Free Aero Race bib shorts use the best chamois Castelli has to date, the Progetto X2 Air.

Like most premium bib shorts, the chamois’ thickness varies between 6mm to 15mm from front to back, providing plenty of cushioning at places where you need them the most.

The Progetto X2 Air consists of 2 layers; the inner layer that comes with bacteriostatic properties adapts to the contour of your skin to provide plenty of comforts and avoid chafing. The outer layer provides all the cushioning needed from road vibrations and the saddle.

Read More : 9 Useful Tips to Prevent (and Treat) Saddle Sores

Giro Air Grippers

Castelli Free Aero Race Bib Shorts Grippers

The semi-transparent Giro Air grippers provide a very wide and solid grip. They provide a uniform grip around the thighs.

More importantly, you won’t feel like they’re cutting through the thighs given that they’re made from soft, stretchable elastic fabrics.

However, take note that since the grippers are both thin and semi-transparent, you’ll have to mind your tan lines.

Remember the sunscreens too.

Fit and Size Guide

Castelli Free Aero Race Bib Shorts Grippers

Castelli’s fit and sizing guide can tricky for some. It can be a hit and miss.

Generally, it’s advisable to go 1 size up based on their sizing table.

I’ve compiled some anecdotes from people I’ve known who have the right fit. You can use these below as a guide.

  • Size S – 165cm, 60kg
  • Size M – 170cm, 68kg
  • Size L – 183cm, 72kg
  • Size XL – 180cm, 79kg

The straps are laser cut and they lie flat on the shoulders when worn.

For some, the straps can feel short and restrictive when standing up. That’s normal because the idea behind a snug strap is you’ll spend most of your time on the bike, where the back is slightly hunched instead of straight.

Castelli Free Aero Race Bib Shorts
  • Fabrics Quality
  • Comfort
  • Grippers
  • Fit and Sizing
  • Breathability

Buy This If...

You’re after a pair of high quality bib shorts for the long and hot days in the saddle. It strikes the perfect balance between quality, performance and price and is hands down the most popular Castelli bib shorts.

Where to Buy

The Castelli Free Aero Bib Shorts is available at the online stores below:

Frequently Asked Questions

1. Are there cheaper Castelli alternatives?

You can never run out of alternatives when it comes to Castelli bib shorts. There are 5 cheaper alternatives to the Castelli Free Aero bib shorts.

The Castelli Inferno and Castelli Endurance X2 bib shorts are other cheaper alternatives that still use the premium Progetto X2 Air seat pads. They differ in the types of fabrics used.

Going down further Castelli’s offerings, there are the Velocissimo, Volo, and Evoluzione 2 bib shorts that are more wallet-friendly.

Read More : The Best Cycling Bib Shorts

2. Is there a women's specific version?

Yes, there is!

The women edition retains all the features and materials used from the men’s version except for two things.

The cut is a women-specific fit, comes in smaller sizing with straps strategically placed so that it doesn’t get in the way. It also uses the Progetto X2 Air Donna seat pad to provide support where you need it the most.

3. How long will it last me?

One of the main concerns about paying a premium price for bib shorts is the durability. Keep in mind that all premium bib shorts are made using delicate fabrics and materials which are meant to be high performance.

With proper care, they will last a longer time. Pay close attention to the washing labels.

Generally, I would hand wash and hang dry my bib shorts. I wouldn’t want my pair of expensive bib short to be spinning in the laundry at 1000rpm, even if its placed in a bag.

Dan Matthews

Dan used to race competitively in the amateur ranks until his mid-30s. He's married with 3 kids aged 5, 7, and 10. When not riding or writing, you can find him obsessing himself in his latest hobby, scuba diving.