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  • Castelli Free Aero Race Kit Version Bib Short - Men's
  • Castelli Free Aero Race Kit Version Bib Short - Men's
  • OptionsCastelli -
  • Castelli -
CastelliFree Aero Race Kit Version Bib Short - Men's
Sale 35% Off$129.95 - $149.98

Item # CST00K5

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  • Black/Dark Infinity Blue, XL ($129.95)
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Item # CST00K5

Free speed, good looks.

Castelli complements its Free AR 4.1 Jerseys with a pair of matching bib shorts displaying the classic, clean aesthetics that have long defined the brand. Devoid of clashing sponsor logos and bright graphics, the Free Aero Race Kit Version Bib Shorts feature the full range of Castelli's achievements in fabric technology, ready to stand out on dozens of start lines with impeccable fit and clean, aerodynamic design.

To put it simply, if you're going to be racing in your Castelli duds, the Free Aero is the kit you'll want. Every feature of the short was designed with racing in mind, from the dimpled, wind-cheating Vortex fabric on the outer thighs to the minimal Carré-engineered bib straps. That being said, Castelli has never neglected comfort in favor of race-day performance. On the Free Aero's inner thighs, stabilizing Forza fabric, which contains 38% Lycra, promises hours of breathable support to your muscles, while the Free Aero's wide, supportive Doppio V waistband holds everything in place as you stretch out over the bars to make a move off the front.

Delving into the Free Aero Race Kit Version's chamois, you'll make good use of the Progetto X² while racing at a blistering cadence or logging serious training miles, seeing it's trusted by the pros logging over 30,000 kilometers per year. To put that into perspective, 30,000 kilometers winds up being well over 18,000 miles, which is probably more mileage than you drive in your car, even with all the road trips to cycling destinations and your daily commute to work thrown into the mix. Castelli employs 10 separate components that take 12 different phases of engineering before it's ready to be mated to these bib shorts. And to prevent any chafing from taking place, you'll find a seamless, bacteriostatic layer that sits softly against your skin to eliminate any irritation whatsoever.

  • Matching bib shorts for Castelli's Free AR 4.1 Jersey
  • Designed for competitive racing and long training miles
  • Vortex fabric is dimpled to reduce drag on the road
  • Forza fabric along inner legs to stabilize muscles
  • Progetto X² chamois with seamless top layer for comfort
  • Carré-engineered bib straps are minimalist in shape
  • Wide, supportive Doppio V waistband
  • Reflective elements along the rear
Tech SpecsSize
Tech Specs
[legs] Vortex dimpled fabric, [inner legs] Forza
race (form-fitting)
Progetto X² Air
lie-flat bib construction
Leg Gripper
GIRO Air mesh-like gripper elastic
reflective details on back
Recommended Use
road cycling
Manufacturer Warranty
1 year


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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Avg. ride time: 11h 13m per week
  • Average ride time is based on Strava activity over the last 3 months. Give your reviews credibility by connecting your account.

Very nice bib shorts

  • Familiarity: I've used it once or twice and have initial impressions
  • Fit: True to size
  • Size Bought: Medium

High quality shorts.

Seemed kinda long on the thighs when first tried on at home but once riding they somehow fall into place at a more normal length just right without bunching. Rode a 100 miles in them and forgot all about them. Recommended.

Not Sure whats up with Castelli's Sewing

  • Fit: Runs small

I ordered these shorts and had high hopes as I like the Nanoflex shorts for colder weather stuff. The chamois foam was balled up in between the fabric and sewn in weird with tons of wrinkles down the legs. I ended up just returning them. :(

I have found same problems in sewing, A super product, but it has had that flaw as of late. They changed manufacturing source, Dominican was really good, but to save a buck they moved east

Agree with Chris, and Tim below, the sewing is really bad on these. Especially for such a high end product. The fit and performance is just as great as it has been for years. But the stitching is a total mess. I had stitches already coming out during the first wear and after a few more times, it's almost opening on a seem on the rear.