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  • Castelli Free Aero Race Short - Men's
  • Castelli Free Aero Race Short - Men's Back
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CastelliFree Aero Race Short - Men's

Temporarily Out Of Stock

Item # CST005J

Don't get too bummed. This item is on the way and will be available for purchase as soon as it rolls into the warehouse.

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Bib-free wind dodging.

Earlier models of Castelli's Free Aero Race Shorts had the same effect on summer kit as the revolutionary Gabba jerseys had on winter tops, completely re-writing the script of what cycling clothing can — and should — do. With this new model, Castelli has not only made significant advances in moisture management, compression, and aerodynamics, it's also brought a bib-free model to those cyclists who prefer an unrestricted fit.

Like its bibbed brethren, the Free Aero Race Shorts are designed to cheat the wind, reducing power output requirements by a claimed 10 watts at 50 kilometers an hour. The secret to these gains lies in how the shorts manage airflow across their multiple boundaries and textures — most obviously via the dimpling across the shorts' outer plane. Like with a golf ball or some deep carbon rims, these dimples manage the turbulent lamina of air that runs along the shorts' surface, preventing its premature release into pockets of drag-inducing dead air.

The shorts also keep the beloved Progetto X2 Air Seat Pad, which returns from last year's version with only one minor change. Its surface is softer, which means it now presents a more gentle face to your perineum. It retains its bacteriostatic properties, seamless construction, four-way stretch, and ventilating, perforated foam layer. The perforated viscous comfort inserts also enjoy an encore performance, so your sensitive areas will enjoy riding over all manner of terrain.

Those may be the only returning features of the previous model — not even the materials used were safe from Castelli's obsessive need to tinker. The seat and front of the shorts both feature fabrics designed for durability and cooling breathability, respectively, and the entire body is 30% Lycra for a fit that strikes a balance between compression and unrestrictive movement.

Last year's model featured Castelli's upgraded Giro3 integrated grip bands at the hem, but it shouldn't surprise you at this point that Castelli couldn't leave well enough alone, upgrading these yet again. The new Giro Air has the same perfectly flat, stay-in-place grip, but with less mass, which no doubt contributes to the claimed overall weight loss of 17 grams and definitely reduces the aerodynamic footprint. The new band is wider, almost equaling the length of a typical Euro-slammed road stem, and every square millimeter of the material acts as the gripping agent. No silicone gel print here.

The lower mass means the leg bands are also pretty transparent, which may initially be a turn-off, but will likely take off as it appears in the pro peloton. In this case, it's important to note that "pro" isn't short for "UV protection," so we recommend a bit of sunscreen applied a few minutes before suiting up. For low-light situations when UV damage isn't an issue, the shorts also incorporate some reflective elements to help keep you visible.

  • Aerodynamic race fit
  • Progetto X2 Air chamois
  • Giro Air leg grippers
  • Reflective elements


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.

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  • Familiarity: I've used it once or twice and have initial impressions

I have a 42" waist and the 3X is more for someone with a 36" waist. Also, the chamois is for a small crotch and a low mass butt. Other than that, it is made really well and should be super comfortable

Terrible sales policy

  • Familiarity: I returned this product before using it

I received these shorts among many other items today from Comp Cyclist. I do most of my shopping online, so I've made it a habit to check the items before opening them.

Low and behold the package that contained the Aero race shorts, was packaged in differently. The package it was in had clearly been cut open and had a returned item inside. What's more disturbing, is that the item appears to have been used and washed then returned.

The most discouraging part, is that Comp Cyclist decided to restock and resell this item instead of marking it as defective. What a joke, seriously- take some pride in your work don't do this to people. I'm tempted to return the whole order based on Comp Cylclist's negligence.

I've attached a photo, so there's no confusion. The package on the left contained a balled up pair of used Aero Race shorts. Thanks, Comp Cyclist!

Terrible sales policy

Castillo free aero shorts

  • Fit: Runs small
  • Size Bought: X-large

I bought the recommended and they were to . Small I have wore them about 6 times and they still don,t fit right not worth the money ,don,t buy them you might be mad get them

Worth every penny

    These are my new favorite shorts on my long rides. Super comfy. I would go with a size bigger than what you normally wear. Can't wait to add more to my collection.

    Exceeded my expectations

    • Familiarity: I've put it through the wringer
    • Fit: Runs small
    • Size Bought: Medium

    I will begin with buying at least 1 size larger than you normally wear. I am 5'6" 138lbs and mediums are tight! After reading reviews I was unsure of spending so much money on a pair of shorts. After my first 35 mile trail ride, I ordered a second pair!!! These shorts are amazingly comfy in all aspects. Love them.

    Great Shorts!

    • Familiarity: I've used it several times
    • Fit: True to size

    These are, without doubt, the most comfortable shorts I have worn. I will also say they are true to size. I normally wear a large, but was hesitant to order large as I had read so many reviews indicating they run small. When I first took them out of the package, I thought they might, indeed, be too small. But, when I put them on, they stretch nicely and fit perfectly. There is no binding, rubbing or the feeling of restriction. Ventilation is good and they are cool. They seem well made. However, contrary to the picture, showing "Made in Italy" mine were made in El Salvador. However, the workmanship appears good.

    Too small

    • Fit: Runs small

    The sizing on Castelli short has gotten much smaller over the past few years. The last pair of bibs I bought needed to be XL's instead of the Med. I usually wear. The last pair of shorts I bought were L, but probably should have been XL's. In the past I have worn mediums. I am 5'6" and 165lbs so for me to need XL's does not seem right. Still love the performance and the Scorpion logo. Castelli needs to check their sizing.

    Castelli home run with the Aero Free!

    • Familiarity: I've put it through the wringer
    • Fit: True to size
    • Size Bought: Large

    If you're like me, you don't like bib shorts, so options are few and far between. I started buying Castelli products about a year ago, beginning with a pair of these Aero Free Race shorts and was immediately sold on them. They are fantastic in every way! Extremely comfortable and feel very light weight, ie "Free". I have two pairs of the race shorts, and one of the endurance. The endurance has the same chamois, but the short material is a bit thicker and doesn't have the same light weight feel, and the gripper material around the leg cuffs feels more rubbery than the Aero Free. Don't let the "Race" name scare you, they're fine for everyday riding. I highly recommend them to anyone!

    bring last year's model back

    • Familiarity: I've used it several times

    i love last year's model so I decided to continue to support Castelli's effort, but wrong decision. maybe they need to leave the perfection untouch. I disliked the wider leg grip and the chamois seems a bit wider. The fit just was not the same as last year's model. I would like buy another one.. until they change it back.

    Castelli shorts

    • Familiarity: I've put it through the wringer

    I purchased these for the quality and durability and was not disappointed.
    Definitely worth the price.

    These run small. look at the size chart.

    • Familiarity: I've put it through the wringer

    I liked my last Castelli shorts so I am back for another. Last time I got 2XL and they fit a little tight. These were 3XL and were as tight or tighter.

    consider size bigger

    • Familiarity: I've used it once or twice and have initial impressions

    I normally order and wear large, they fit just perfect.
    But, this one is small, I should have ordered XL.
    I am 6 ft & 170 lb. Everything except size is better than perfect.

    Agreed on the sizing for Castelli. I have purchased their products previously and found that you need to buy one size up from what you would normally select (ie Pearl Izumi, Specialized). I'm also 6'1 and 170. I have the XL jerseys/shorts and they fit well.