How to Choose a Hydration Pack for Mountain Biking

When choosing a hydration pack you need to consider many different factors. For instance, how much water you want to carry, how much other storage space you’ll need, and how you want the pack to fit. I’m going to walk you through some of the main points you’ll want to consider, and offer a few suggestions to help you decide on a product that’s right for you–whether it’s your first or fifteenth hydration pack purchase.

An Intro to Hydration Packs

What exactly is a hydration pack? It’s basically any backpack that is designed to hold a reservoir full of water (sometimes called a bladder), which connects to a hose that is easily accessible while riding (or participating in whatever activity you choose). There is generally a separate compartment specially built in for holding the water to keep it from moving around or creating uncomfortable pressure points on your back as you’re wearing the pack.

Some of these packs don’t have space for much more than a water reservoir, while many others have plenty of room for items such as tools, spare tubes, extra clothes, a camera, food, and even camping gear.

There are many different options when it comes to storage capacity, fit, and special features, so I’m going to break down some of these different variables to hopefully help you figure out what might work best for your needs.

Water Capacity

The first thing you’ll want to figure out is how much water you need and want to carry. Keep in mind that you don’t always have to fill up the bladder completely, so it might behoove you to buy a pack with a water capacity that is slightly larger than what you think you’ll need for everyday rides, but what you might want for the occasional long ride.

Of course, the tradeoff is size and weight–even with an empty reservoir, a pack with a larger capacity will carry a larger footprint and weigh more than a pack with a smaller capacity.

Typically, bladders are one of three sizes: 50oz (1.5L), 70oz (2L), or 100oz (3L), though the smallest size isn’t very common anymore. Most hydration packs have a dedicated area for the bladder, which is usually designed around a particular bladder size and advertised as such, but also may be able to accommodate different sizes. For instance, sometimes it is possible to make a larger-than-intended reservoir work, but it’s not a good idea to count on that when buying a pack.

Bladders come in a variety of shapes and sizes.
Bladders come in a variety of shapes and sizes.

This dedicated reservoir area is usually separated from the rest of the pack, and a padded section between your back and the reservoir adds comfort and minimizes the sensation of a bulge of liquid against your spine while pedaling.

So, how do you decide how much water storage space you need? I find that more space is better than less, because I like to be prepared for long rides and I tend to drink a lot, especially in the warmer months. I also ride small frames, which usually only have one bottle cage mount, so I have no qualms about carrying a slightly bigger pack. As a result, I personally use a 100oz water capacity. But if you rarely or never ride for more than a couple hours, find that you just don’t drink very much, or have other water storage options (bottle cages, etc.) and will only be using the hydration pack to supplement that water, you should be able to get away with a smaller pack.

A Word About Reservoirs

Not all hydration pack reservoirs are the same. Aside from being different sizes, they also vary in their rigidity, shape, and integrated features. Some reservoirs are soft and pliable, while others are more rigid and hold their shape. Softer reservoirs tend to sag inside the hydration pack, unless there are specific hooks or holders to keep them in place, which most packs will have if they are designed for that type of reservoir. Since some packs are sold without a bladder, just made sure your pack and bladder are compatible so that you aren’t dealing with unnecessary annoyances.

platypus soft reservoir photo by maureen
This Platypus reservoir is soft, but attaches to the pack via clips to keep it in place and eliminate sag. Photo: Maureen Gaffney.

Bladders also have different fill and closing mechanisms. Some have a circular screw-on lid (like the Osprey pictured below), while others have a Ziplock-style or roll-top closure. I’m not sure that one style is better than another; it all depends on your personal preference. I will say that a large opening on one end (see the Hydrapak below) makes cleaning and drying out your reservoir much easier.

osprey bladder photo corey maddocks
This Osprey reservoir is on the stiffer end of the spectrum. Photo: Corey Maddocks.

This Hydrapak reservoir is easy to clean due to its large opening on one side. Photo: Jeff Barber.
This Hydrapak reservoir is easy to clean due to its large opening on one end. Photo: Jeff Barber.


Though it’s called a “hydration pack,” water capacity isn’t the only important factor to consider when choosing a bag to take mountain biking. Storage space is highly variable, and ranges from barely enough room for a phone and keys to a full-size backpack that can hold everything from camping gear to camera equipment.

A minimal pack might be the ticket if you have ample frame storage on your bike, and you want to carry plenty of water on your back and leave frame bags for other supplies. If you have a small frame and can’t fit a lot on it, you’ll probably need a larger pack to compensate. If you enjoy photography more than the average person and want to take a large camera and multiple lenses along with you while riding, you may want to look into a backpack specifically designed to carry photography equipment.

Most of us fall somewhere in the middle, and want a pack that will hold plenty of water, as well as a few other items, such as tools, food, and an extra layer or rain jacket. The majority of hydration packs on the market are designed with these exact needs in mind.

Many hydration packs include small pockets for organization, and some come with a tool roll. Photos: Corey Maddocks
Many hydration packs include small pockets for organization, and some come with a tool roll. Photos: Corey Maddocks


The fit of your pack is not something to be taken lightly. After all, the last thing you need is to be uncomfortable as you’re barreling down sketchy descents, slogging up a killer climb, or just trying to enjoy a peaceful day on some singletrack.

There are a couple different styles of hydration pack on the market. The majority of packs are similar to a typical backpack in that they are attached to you mainly via two shoulder straps. Most of the time, they’ll also have a chest strap and hip belt to customize the fit and keep the bag from bouncing around as you’re in motion.

Some hip belts are padded and include small pockets for easy access to essentials. I usually keep my phone/camera in one of my hip pockets and a multi-tool and energy chews in the other. Other hip belts, typically on smaller packs, consist of just a thin strap that goes around your waist to keep the bag in place.

A slightly different style of hydration pack is the “lowrider” or “lumbar reservoir,” both of which coincidentally have the initials “LR” and mean the same thing–the weight of the pack, the water, and other gear is kept on the lower back and hips, relieving the mid-back from any burden. This is a great option for people with back issues that can’t wear a regular pack, or people who just prefer this type of weight distribution. Some of these packs are basically a glorified fanny pack, while others still have shoulder straps.

What about women’s-specific packs?

The Womens Osprey Raven 14L. Photo: Daniel Palma

Women’s-specific hydration packs tend to be shorter, and sport ergonomically-designed straps to accommodate a different body shape, especially in the chest area. That being said, just because you’re a female doesn’t automatically mean you need a women’s-specific pack. Just like with bikes, “women’s-specific” means a certain set of variables will be generally different than a “unisex” model, and those characteristics may or may not work for individual women.

Some women have long torsos, and like the fit of a unisex pack better. That being said, there may be some men out there who find that a women’s pack fits better, and there’s nothing wrong with that. If you’re unsure, it might be a good idea to head over to your local bike shop and try a few on before you buy.

Other Factors

Waterproofness: Some bags are more waterproof than others. Some hydration packs also include a waterproof cover that can be pulled out in case of rain. This might be an important consideration if you ride in wet conditions on a regular basis, or if you’re carrying sensitive equipment (like a camera).

Availability of Parts: If you travel to other countries a lot for bike adventures, it is worth looking into the vailability of parts, such as bite valves, for certain brands. CamelBak is probably still the most widespread hydration pack brand across the world, but other companies, such as Osprey and Dakine, are quickly growing in popularity.


There is a lot of information to take in when trying to choose a pack, and there are so many different packs on the market that it might seem impossible to decide. I’ve put together a list of a few highly-ranked options from our Singletracks gear review database, as well as a couple personal favorites.


CamelBak Rogue: CamelBak was one of the original innovators in active hydration, and they continue to be a dominant player on the scene. The Rogue is a sleek, compact pack that holds a 2-liter reservoir, as well as basic essentials, such as a tube, pump, multi-tool, phone, and keys. Stretchable side panels allow for expansion and can accommodate items like an extra, packable layer. This is a very highly-rated pack amongst users, mainly for its simple, lightweight, and breathable design, small back footprint, and comfort. However, if you tend to pack a lot or go on a lot of longer rides, this pack might not offer enough storage space. MSRP: $70 (Available at Amazon and other retailers)



CamelBak M.U.L.E.: The M.U.L.E. is a classic, considered to be the “original 3-liter hydration pack for mountain biking,” and to this day, it continues to get great reviews. It offers 9 liters of storage in addition to the reservoir–enough for tools, a jacket, and ample food for a long day on the trail. Users attest to its durability, comfort, and well-designed pockets. MSRP: $110 (Available at Amazon and other retailers)

The Osprey Raptor. Photo: Corey Maddocks
The Osprey Raptor. Photo: Corey Maddocks

Osprey Raptor: This is a favorite pack in my local cycling community, for good reason. The current models are the 10 and 14, which both have a 3L water capacity and plenty of storage without being bulky. The 10 probably offers ample-enough space for many people, but if you find yourself heading out on longer rides on a regular basis, go with the 14 for some extra room. Corey reviewed the current design’s predecessor, the Raptor 6, back in 2014. And ladies, if you’d like a women’s-specific fit, check out the Raven. MSRP: $150 (Available at Osprey and other retailers)

Dakine Drafter: This seems to be a favorite pack amongst members of the Singletracks team. Aaron, Greg, and Syd have all reviewed different versions of this pack over the past years, and all had plenty of positive things to say. This pack also receives almost 4.7 stars out of 5 in the user reviews section of the Singletracks site. Its 18 liters of storage and 3-liter reservoir offer plenty of water and space for whatever you need to take along on an all-day ride, without stepping into the realm of being too cumbersome. You can buy this pack with or without the Hydrapak reservoir, which features a sliding top closure and is completely reversible for hassle-free cleaning. MSRP: $135 (Available at Backcountry and other retailers)


Lowrider style:

CamelBak Solstice 10LR:  It offers plenty of storage space and the 3-liter bladder has been enough water for almost every ride I’ve done (except a couple long ones in extreme heat). I really like the weight distribution of the lowrider-style pack. The one con I have figured out after a few rides in very heavy downpours is that it’s not entirely waterproof, but the insides do stay dry in light rain. I personally really like the wide waist belt and large hip pockets, which offer added comfort and extra storage. MSRP: $130 (Available at Backcountry)

Mountain Bike Hip Packs

In blue. Photo: Chris Daniels

Dakine Hot Laps 5L: The Hot Laps from Dakine has an overall carrying capacity of five liters, and includes a two-liter Hydrapack bladder housed in the main compartment. The reservoir hose wraps around the waist with a length-adjusting magnetic lock.

While there is no interior organization in the main compartment, the tool compartment has four pockets in various sizes and closures. Carrying capacity extends beyond the two main chambers with a very small stash compartment on the hip belt, daisy chain webbing in the rear, and two outer straps. The waist strap features a 1.5-inch buckle and is adjustable on one side, while bilateral compression straps can be used to cinch the load down as necessary. MSRP: $70 (Available at Jenson USA and other retailers)

“So how do I choose?”

Whether you’re looking to buy your first-ever hydration pack or upgrade to a new or different model, just take a moment and think about what sort of riding you mainly do, what features are most important to you, and how much money you’re willing to spend. Check out the Singletracks review database for some more ideas, as there are plenty of excellent packs that I didn’t mention here.

Of course, hands-on experience is better than just looking at a picture and specs, so if you’re uncertain, head over to your local bike shop and try on some different packs. You could even bring along the ride gear you usually carry and see how it all fits in whatever pack you’re thinking of purchasing. If it feels comfy, great! If it doesn’t feel comfortable in the store, it’s probably not going to be comfortable on the trail.

Many pack companies also offer demos at bike events so that you can actually try a pack out on the trail before buying, which is an excellent idea if you have the opportunity. Another option is to try out a friend’s pack if they own one that you are interested in purchasing.

There are so many choices, and everyone’s needs are different. You just have to figure out what works for you!

Photo: Daniel Palma

Article Updated on November 7, 2019 by Jamieelee Garcia