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Mountain Bike Hydration Backpack 6 L 520

Sale price: $30.00 Regular price: $39.99

Go mountain biking for up to 4 hours with this water bladder: with 2 liters of water and a 6-liter capacity, this bag is the perfect companion for mountain bike touring.

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Sale price: $30.00 Regular price: $39.99

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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: 8300157

Product Videos

Product Features

A photo of the Mountain Bike Hydration Backpack 6 L 520 in use

Mountain Bike Hydration Backpack 6 L 520 | Our team developed this water bladder to keep you hydrated for MTB tours of up to 4 h.

Go mountain biking for up to 4 hours with this water bladder: with 2 liters of water and a 6-liter capacity, this bag is the perfect companion for mountain bike touring.


A usable volume of 6 L and a 2 L water bladder: stay hydrated for 2 hours.

Multiple compartments

1 large pocket, 1 water bladder, 4 small inner pockets and 1 outer pocket


Adjusts with the shoulder straps, the waist strap, and the chest strap.

Carrying comfort

Back made of perforated foam and straps made with mesh for ventilation.

Product Customer Reviews

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Mountain Bike Hydration Backpack 6 L 520
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It's good, but if there was one thing that would make it better, is having a 2 way zip on the larger outer pocket. Stuff falls out when you open it. Also I unfortunately got given the old water bladder and styling which isn't what was advertised or I think as good.

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ST 520 hydration backpack 7 L ROCKRIDER

Great hydration backpack for long cycle rides.

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Good price and capacity

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Awesome convenient bag

Very convenient, lightweight, easy to pack and to handle. perfect size!

Rockrider hydration pack

This is ideal for cycling lightweight comfortable and has load of pockets for storage loads of room to pack for items

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Great size hydration backpack

Just the right size to carry enough fluids & also all your cycling essentials

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Bought for my husbands birthday and hes over the moon with it. Great size, comfortable to wear and the hydration pack is great

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Total Bargain

Superb piece of kit and I actually couldn't believe this was only £30.00 in UK after trying it. The 2L hydration pack reservoir and tube are great for longer rides when the 1L mounted downtube-bottle isn't quite enough. Good quality and feels like it will last. Plenty of space for a spare Tube, Waterproof jacket, First Aid, Phone, Keys, Lube, Allen Keys, tyre pump with the Hydration pack filled to 2L. Alongside all that, was able to fit a Giro Switchblade Chinbar, so perfect for Enduro and XC riding. Waist straps and chest straps fit well. Only downsides are; I'm not sure on how well waterproofed it is, so may consider buying a cover for it. If you fill the Hydration pack up full, the pack sits very straight against the back instead of flush. Not a major problem as it's still comfy enough but that's probably where the more expensive Camelbaks pull away. Otherwise, Its absolutely superb for the price, looks and functions like something £50 more. Don't bother buying a Camelbak unless you want extra comfort and perhaps better waterproofing. This has about 90% of a Camelbak's features for a fraction of the price. It's won MTBR awards for a very good reason, outstanding value for money!

MTB - Backpack

You will struggle to find a better piece of kit. The price is an absolute bonus! Classic Decathlon brilliance

Excellent hydration pack.

Been using it for almost a year now. Plenty of water for rides and the bladder is designed well which makes it easy to clean. Plenty of other storage for bits & pieces. Love using this pack.

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Delivered a used pack!

Utterly disgusted to have taken delivery of a USED item - Water still inside the bladder and hose, with a dirty mouthpiece and hair/debris inside the pockets. Given the current pandemic which is spread by droplets of saliva this is honestly the worst experience I've had buying online. How this was not checked during the returns process is beyond me.

Good kit

Only used once so can’t really comment

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I love this bag so much that I don't only use it when I'm out on the MTB, I use it all the time on days out. It is the perfect size for keys, phone and purse, plus other bits and bobs. Sure you couldn't fit a change of clothes, lunch etc in it, but for a morning out or a ride on the MTB, it is the perfect size and it doesn't make your back all sweaty. It is very good quality, I am very happy with it.

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I cycle for about 5 to 6 hours each time 3 or 4 times a week and it holds my water snacks and repair kit very well.

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Brilliant design,however

A really well thought out pack. Just the right size for carrying a pump, multi tool and a few spares and room for a waterproof top, however the zip has failed on mine after not a huge amount of careful use

Thank you for taking the time to post a review of the bag. I'm glad you find it to be useful and practical. I'm sorry to read that the zip has failed. We provide a 2 yr warranty on all of our own brand items. Pleas return it to us if you purchased withing this period with your receipt and we will replace the bag for you.
Peter, Cycling Manager, DECATHLON
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Additional Product Information



  • 100% Polyester cationic

Main fabric

  • 50% Polyester cationic
  • 50% Polyamide

How do i maintain my water bladder?

We recommend that you rinse out and dry the water bladder after each ride. To make it easier, use the cleaning kit with the bottle brush and a drying rack (code: 5935596). It is important to clean the bladder and hose.

Bring it with you...

This hydration backpack allows you to store your phone, a pump, an inner tube, tire levers or a repair kit, a multi-tool, a compact rain jacket, and a granola bar. Multiple pockets let you pack all your essentials in your bag!

Bring with you ...

This hydration backpack allows you to store your phone, a pump, inner tubes, tire levers or a repair kit, a multitool, a chain rivet extractor, a rain jacket, and granola bars.



Storage instructions

Once clean and dry, keep your backpack and water bladder in a dry place and away from direct sources of heat. Clean by hand in soapy water.

Care instructions

After each outing, rinse and dry the hydration bladder. Use the brush and dryer cleaning kit (item 631 585). Wash the bag by hand using a sponge and soapy water.

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
  1. product-research

    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

  4. laptop-checkout

    Minimal retail footprint

    lowers overhead and indirect costs


Size Guide Visual