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Men's Mountain Bike Undershorts EXPL 500 - Black

Sale price: $10.00 Regular price: $34.99

With its thick pad and breathable fabric, the ergonomic foam pad on these men's undershorts absorbs vibrations and prevents chafing and irritation.

Color: Select a color
Size: Select a size
Sale price: $10.00 Regular price: $34.99

Free shipping over $49

Final Sale: No returns or exchanges

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San Francisco, 735 Market St. Options

Select an available color and size to see options.

Model: 8580800

Product Features

Men's Mountain Bike Undershorts EXPL 500 - Black | These mountain biking undershorts were designed for your mountain biking rides lasting 3 hours on average

With its thick pad and breathable fabric, the ergonomic foam pad on these men's undershorts absorbs vibrations and prevents chafing and irritation.

A photo of the Men's Mountain Bike Undershorts EXPL 500 - Black in use
A photo of the Men's Mountain Bike Undershorts EXPL 500 - Black in use

Seat comfort

Ride comfortably for up to 3 hours with the ergonomic foam pad (13 mm).

Moisture wicking

Actively wicks away perspiration to the outer surface for quick drying


Fitted cut without compression, very elasticated waistband


Elastane in the fabric to guarantee ease of movement.


You just need one: these undershorts are compatible with our men's MTB shorts


170 g in size L.

Questions & Answers

Product Customer Reviews

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Very good

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Great/ I love it.

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Excellent but

Great item but a little tight at the thighs, I took an L and an XL, the elastics on the thighs are the same, only the one at the waist changes. Too bad when you have muscular thighs.

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Very good product !!…

Very good product !! Essential for mountain bike sessions lasting more than an hour.

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Does the job well.


Always satisfied

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Comfort is not good

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Very small size

Take two sizes larger because the thighs will not fit. Average seat.



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perfect for the trainer, always buying different outdoor shorts size L for 175/75 kg, this time XL

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MTB or cycling shorts

Ok a little small for an xl

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Nice one

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Excellent product

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Additional Product Information


Foam: 100.0% Polyurethane ; Main fabric: 80.0% Polyamide, 20.0% Elastane ; Yoke: 86.0% Polyester, 14.0% Elastane ; Lining: 100.0% Polyethylene

In a nutshell

Pad thickness: 13 mmPad density: 100 kg/m3Pad firmness: 25 KPa

Undershorts support.

Bibless undershorts can be much more practical. But do you get enough support?To guarantee the support you need, even without straps, we have made a pair of undershorts that hugs your body just like boxers. The elasticated waistband adapts to fit you and stays in place with no adjustment needed.

A second skin with comfort to boot.

The pad has been designed for more regular users looking to progress in MTB. The support foam is also soft but more dense. It protects pressure zones for up to 3 hours. The foam is soft and the stretchy outer layer hugs the cyclist's body so the pad can follow their movements. Foam thickness: 13 mmFoam density: 100 KG/m3Foam firmness: 25 KPa

Shorts, undershorts.

Undershorts are to MTB what kilts are to Scotland: you wear them against your skin!To avoid chafing, we therefore recommend changing them and washing them as if they were underwear.And when you're riding, your shorts and undershorts should never be attached.Why? Because each has their own role to play:- The undershorts stay in place for comfort and support.- The shorts move with you for better freedom as you cycle along.

Care instructions

You can find detailed info on looking after your mountain bike clothing on our website

Product tests

Our team of product designers based at the B'Twin Village in Lille is continuously working to make cycling more comfortable for our users.Our obsession is to create products that meet the specific cycling needs of our users and eliminate hindrances to a good cycling experience.

Product testing

Our engineers always have real riders test all our products in real conditions. These tests round out our lab tests and let us validate all our products before they hit store shelves.

Storage instructions

Store in a clean and dry place.



Superior quality. Unbeatable prices.

For 40 years, Decathlon has delivered the best value in the retail sports industry by offering high-quality, sustainable and cost-effective products.

Decathlon makes the difference
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    Research and development

    delivers high-quality cost-effective products

  2. State-of-the-art production processes

    minimize manufacturing costs

  3. Optimized supply chain

    reduces retail prices

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    Minimal retail footprint

    lowers overhead and indirect costs


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