The best MTB bib shorts may not be at the top of the shopping list for many mountain bikers, but if you are doing long days in the saddle a set of the best MTB liner shorts can make a massive difference in comfort.
The key advantage to wearing a pair of MTB liner shorts under your best mountain bike shorts is the pad, or chamois, that's sewn into the bib liners. These pads are specifically designed to add comfort and support when riding, as well as wick moisture away too.
The best MTB liner shorts often have other practical features too, namely storage. As riders looked for alternatives to backpacks, brands quickly realized adding pockets to a pair of bib shorts was a great way to increase storage without having to resort to a bag or hip pack.
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With a little on-bike storage and a few items tucked away in your pockets, it's possible to hit the trail without being loaded down by a backpack.
Keep reading as we share our pick of the best MTB liner shorts for the trails
Meet the tester
Why trust BikePerfect Our cycling experts have decades of testing experience. We'll always share our unbiased opinions on bikes and gear. Find out more about how we test.
Graham is all about riding bikes off-road. Based in Edinburgh, he has some of the best mountain biking and gravel riding in the UK right on his doorstep. With almost 20 years of riding experience, he has dabbled in downhill, enduro and, most recently, gravel racing.
Best MTB liner shorts
Specialized was one of the first brands to integrate pockets to bib liners as part of its SWAT (Storage, Water, Air, Tools) series which saw a bunch of cargo-carrying alternative options across clothing and bikes, many of which have now become commonplace.
Specialized’s mountain liner features a huge amount of pockets with one on each leg, two angled rear pockets with a deeper center pocket, and a zipped valuables pocket on the right-hand of the rear pockets. An impressive array that should offer storage options for almost everything you need on the trail. The rear pockets are half-sewn onto the body of the shorts too which allows them to sit lower without interfering with your baggy short waistband although we do find this design results in a bit more movement in dynamic riding situations. Nothing has escaped, though, and the zipped pocket is a nice addition to ensure your most important valuables are securely stowed.
The shorts are made almost entirely of a VaporRize mesh material to stop overheating from becoming a problem. We found the fit to be very comfortable although the shoulder straps don’t have much stretch to them which makes them feel a little more restrictive. On the bike, this is almost unnoticeable and we were comfortable even when our hours in the saddle were hitting double figures. Upfront there is a side access flap for easy nature breaks and the shorts feature popper fixings to integrate with Specialized’s baggy MTB shorts. The thick but firm chamois inside follows Specialized’s Body Geometry ethos and has also been designed to pair perfectly with its range of saddles. In hand it feels pretty different from the other softer stretchier pads, though in use we found it still offered a high level of comfort and support.
Get a more detailed lowdown on the Specialized Mountain Liner SWAT shorts in our review.
Endura has been making great mountain bike-specific gear for ages, as well as road and gravel kit too. So it's no surprise that the Singletrack bib liner 2 has quickly combined these to become one of our favorite bib liners.
The rear pockets are huge, and while the lineup of three along the back might not be the easiest to reach into while riding, they are very deep and can easily store everything you need securely. They also have a hydration/back protector pocket, although you will need to source your own bladder.
The fit is pretty deep with the bibs coming up quite high around the body, it's very comfortable giving the feeling that they are locked in place. We were worried that the extra coverage might make them more susceptible to getting hot but that hasn’t been the case. Endura has developed its own chamois for the Singletrack liners, based on the 500 series road pad, we found the 500 Mountain to be comfortable and supportive. Endura has also added a horizontally cut fly for easy mid-ride toilet breaks.
Read more about the Endura Singletrack bib liner 2 in our review.
Rapha may not have been in the mountain bike game for long, but its off-road kit has been going down well. With Rapha’s background in road cycling, it's unsurprising that its Trail Cargo bib liner shorts are a great option if you are looking for extra comfort in the saddle.
Rapha has leveraged the 15 years of bib short design and the result is a fit and chamois that is extremely comfortable. The shorts stay in place no matter how out of shape you get on the bike too. Temperature management is good as well, with a long mesh panel up the sides of each leg as well as the mesh construction across the bib straps and across the back.
Rapha hasn’t specced pockets on the legs, likely in favor of maximizing ventilation although there are two angled pockets on the rear which offer easy access. While the rear pockets will happily house most trailside essentials, their depth does mean they aren't great for longer items like small pumps.
For a more in-depth guide to the Rapha Trail Cargo bib liner, check out our review.
Irish outfit Nukeproof are well known for making fun and gravity-orientated bikes, components, and apparel to match. The Blackline range signifies Nukeproof’s workhorse trail kit and sets an excellent performance to cost benchmark.
The Blackline Storage bib shorts have been around for years and have remained almost unchanged the entire time. Perforated upper and flanks help keep things cool in the heat and the casual fit means they are comfortable enough to wear all day. The chamois is very thin which is going to suit pedal up and shred down riders who don't want to feel like they are wearing a nappy, rather than riders looking for comfort for backcountry mile-munching epics.
Both leg pockets are a good size although they feature a stitched partition in the upper elastic despite the rest of the pocket not being separated. While this does hold a gel well for a quicker draw and an instant hit of energy, it can cause other items to get hooked when trying to grab them out in a hurry. The rear pockets are huge although the positioning is great for access, it isn't perfect as they sit pretty low and can hang out the bottom of shorter-cut jerseys. Like the Specialized SWAT liners, I also found they flapped around a lot unless they were under a few layers of clothing or tucked into a waistband – which sort of defeats the point of half-sewing them rather than fully anchoring them.
Leatt’s MTB 4.0 bib liner is new to range but it comes to the market packed with a lot of great features seen on the current best MTB liner shorts. Unlike most MTB bib liners, which are usually modeled on road bib shorts, the MTB 4.0 bib liner is tailored with a shorter leg in order to stop them from interfering with your knee pads which is smart thinking from Leatt.
Made from four-way ECO X-Tract stretch moisture-wicking material they are stretch stitch thread for seam strength and feature a fly opening for easy relief. The material has almost zero compression, which means they are pretty unnoticeable under a set of baggy shorts although not as supportive as other bib liners on this list. Despite the padding of the chamois being more rear-ward orientated, with almost no padding towards the front, we found it to be very comfortable.
There is plenty of storage too, with two leg pockets and three rear cargo pockets. These all feature silicone grippers to keep items in place to stop belongings from leaping out mid-ride. The pockets are a bit shallow, though, and the lack of elastication meant that these are one of the only liners where we felt like items could be a flight risk – with that in mind, we would highly recommend not trusting the Leatt rear pockets with heavy, slippy items like mobile phones. There is also a rear pocket to fit a Hydrapak Horizontal Bladder, or similarly sized bladder, which can be purchased separately. You could use this to store other items, although it's a bit of contortion to get into due to the position of the openings.
While POC is best known for its helmets, it also has a range of MTB and road clothing to match. Part of that range is the Air Layer bib liner which with air in the name, unsurprisingly features a lot of mesh construction.
POC has positioned mesh for all the upper bib sections and down the flanks to increase breathability. The effects are pretty noticeable There is a slightly finer mesh used along the back between the pad and where your short waistband will sit, as well as inside the leg, to add a little more durability and structure. POC has fitted its own VPDS Catalyst pad which has a very obvious contoured shape to it and a decent level of padding.
POC has opted to play the numbers game, rather than size, with its pockets. There are four rear pockets lined across the rear of the back and for me, these sit just above my short waistline. The center pockets are larger while the two smaller outer pockets are almost positioned on the side of the body to give easier access to must-have on-the-move items like snacks. There are two small leg pockets positioned low down too for storing more at-hand items.
How to choose the best MTB liner shorts
What do mountain bikers wear under shorts?
Unless you are racing cross-country, the majority of mountain bikers will choose to ride in a pair of the best mountain bike shorts, or pants. That means if you want to ride with a pad or chamois then you will want a pair of the best MTB liner shorts. You could ride in your regular underwear however they can bunch or have awkwardly placed seams which can cause discomfort. Just in case you don’t know, bib liners, like bib shorts, are designed to be worn without anything on underneath.
It should be pointed out that unless otherwise stated, the shorts in this list are specifically bib liners, not bib shorts, and are intended to be worn under a pair of baggy shorts. Most of the shorts on the list feature mesh panels which are great for keeping you cool, but will be a bit too revealing on their own.
Are padded mountain bike shorts worth it?
Rider preference plays a big part in whether you need bib liners for mountain biking. For those that like to go on long rides then bib liners are a worthwhile investment in order to keep you comfortable after many hours in the saddle. While comfort won't play as much of a role on shorter rides, it's still important. For shorter local rides or a few enduro laps where you don’t need to carry much, having the extra cargo capacity means you might not need to burden yourself with a backpack
What pockets do I need?
The most important pockets to have are the ones on the lower back. These are often great for storing a phone, multi-tool, pump, and little bits of clothing like gloves etc. Many shorts will feature leg pockets too. We usually store softer items like snacks in there as they don't interfere during pedaling and will leave less of a mark if you crash onto them. Obviously, leg pockets are only really practical if you are wearing shorts and can easily pull the legs up.