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CastelliFree Aero Race 4 Limited Edition Bib Short - Men's

Sale 25% OffCurrent price:$149.96 Original price:$199.95

Item # CSTZ7CK

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  • Black/Red, L ($149.96)
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Item # CSTZ7CK

Why We Like The Free Aero Race 4 Limited Edition Bib Short

Designed to cheat the wind, the Free Aero Race 4 Limited Edition Bib Short as it's top-tier short for training and racing. We love it particularly for how well it handles the heat, allowing us to ride in the hottest weather. The Limited Edition designation pertains to the use of colors that distinguish it from the standard Frees. Comfort, aero benefits, and strikingly good looks, all in one package.

Inside the bib, the excellent Progetto X2 Air chamois has a seamless construction, four-way stretch, and impressive ventilation with its perforated foam layer. The Forza material of the legs offers just the right amount of compression to aid in recovery and prevent premature fatigue over rougher terrain. The Doppio V construction allows for excellent breathability without sacrificing support while the suspenders are mostly mesh and utilize lie-flat material on the shoulders. For the leg openings, Castelli trusts its Giro 4 mesh-like grippers to keep the hem in place.

  • Aero and comfort racing bibs for performance-driven cyclist
  • Aerodynamic details net a claimed savings of 10 watts
  • Gently compressive material support muscles
  • Lie-flat grippers and suspenders are sleek and reduce drag
  • Progetto X2 Air chamois is supportive and comfortable
  • Castelli's construction and the fit is honed by its work with professionals

Tech Specs
Material[legs] Vortex, [inner thighs] Forza
Seasonspring, summer, fall
ChamoisProgetto X2 Air
Leg GripperGiro4
Manufacturer Warranty1 year
Activityroad cycling, gravel


Men's Apparel




















































How to Measure:
For best results, take measurements over your underwear.
Measure under your arms, around the fullest part of your chest.
Measure around your natural waistline, keeping the tape a bit loose.
Measure around the fullest part of your body at the top of your legs.
Using pants that fit well, measure the crotch seam to the bottom of the leg.

What do you think about this product?


>Rating: 5

Excellent bibshort

very comfortable for long walks very good fit on the legs the olive color is beautiful and different, like Italian brands you should buy a larger size

>Rating: 5

Fits well, cushions well

I've used it once or twice and have initial impressions
Runs small
Size Bought

I chose a size up from my usual selection as these are meant to be worn snug. They performed well over a weekend 20-miler, and the chamois was up to the task of keeping me well-protected. Highly recommended if you want an aero pair of bib shorts - just remember to order a size bigger than your normal selection.

>Rating: 5

Nice shorts

I've used it several times
Runs small
Size Bought
5` 11"
152 lbs

I'm 5'11" and 152 lb. The mediums fit well except for the straps which were much too short. Returned for the large, which fits well. It could definitely accommodate a larger pair of legs. They are light but comfortable

>Rating: 2

Sadly, I had to send them back.

I returned this product before using it
Runs small

The graphic details around the cuffs and the grippers are super cool and more gray than bright white, but they really need to show you a side view. I was excited about the tech and style. I've rode a 2016 pair of black/gray/white Castelli bibs to death, but with the two-tone sides on these, it kind of looks like you’ve got a women’s bathing suit on over your bibs. That’s just my opinion, but my wife gave them the thumbs down too. From a technical standpoint, the chamois looks extremely plush, but the shoulder straps were way too short to “œlay flat” for me at 6’2” even in an XL.


two stars because you didn't like the side panel "look"? researching current castelli sizing would have indicated an XL at your stated weight. i'm still in my aeros after 2.5 seasons and my only complaint is the chamois has lost some but, the bibs are quality. the straps definitely run short if you are long in the torso.

Thanks for showing that side panel. I'll pass on this one.

>Rating: 5

Best bibs I've ever owned

I've put it through the wringer
True to size
Size Bought
6` 0"
210 lbs

I've ordered and worn out quite a few bibs over the years. The high-end Rosso Corsa Castelli bibs have always felt the best and lasted the longest. They are more expensive but given how long they last they are the most economical by far, not to mention the best performers. The Free Aero Race 4 bibs are the best yet. The straps are more comfortable than the other Castelli bibs I own. The chamois is very comfortable on long rides with plenty of ventilation. Castelli tends to run small but the XL was true-to-size, snug with no sagging anywhere but not so tight that they are constrictive.

>Rating: 5

Typical Castelli Quality

I've used it once or twice and have initial impressions
Size Bought
190 lbs

Simply a great overall bib. It's everything you expect from Castelli. The progetto chamois is super comfortable from any seating position, no odd or uncomfortable feeling from seams in the material, it's very supportive and great compression feel in the legs. My only gripe is that this version of the Aero race bib has a slightly tighter fit than the previous aero race kit versions. The kit version (size large) from 2016 was a perfect fit for me and this version truly feels like a "race fit." It's not so tight that is takes away any comfort or effectiveness, but takes me a bit longer to put on.

>Rating: 5

Super chamois!

I've used it once or twice and have initial impressions
True to size
Size Bought
6` 4"
208 lbs

The chamois in these bibs are great, I've always love Castelli's chamois, and how somehow it's even more comfortable. It magically sits in just the right place, isn't too think, and is insanely comfy on the longer rides compared to some of the other brand shorts I have. These are a "race" fit, so they're super snug, which I like, makes me feel fast and aero. As I'm probably never going to reach 50 kph, unless it's down a hill, the true aero benefits are probably lost on me, but they look fast and that's worth a couple watts right there! I went with XL and the straps feel a bit short. Not like they're digging into my shoulders short, but short to the point they don't lay nice and flat like Castelli intended. I went back and forth on ordering the XL and XXL, after looking at the sizing charts again I'm not sure it would have made any difference in the length of the shoulder straps. Just a heads up if you're a taller rider, that could be an issue you see. Otherwise I wouldn't let it stop you from owning these amazing bibs, especially if you wear a base layer, the strap tension is even less noticeable.