Leatt MTB 4.0 bib liner review – comfortable but careless with your belongings

Leatt’s MTB 4.0 bib liners are well-fitting and comfortable but the pockets let the shorts down

Leatt MTB 4.0 Bib Liner
(Image: © Graham Cottingham)

Bike Perfect Verdict

Leatt’s bib liner has a comfortable fit and a decent amount of ventilation, however, the rear pockets struggle to securely hold items and will jettison your belongings when riding technical trails

Pros

  • +

    Comfortable fit

  • +

    Well ventilated

  • +

    Fly hole

  • +

    Shorter leg plays well with pads

Cons

  • -

    The rear pockets aren’t secure enough for phones, tools, or snacks

  • -

    No bladder hose routing

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Leatt is a South African moto and MTB brand that rose to prominence with its range of body protection and neck braces. Since then they have diversified their ranges to encompass all riding clothing moving to helmets, shoes, and clothes too.

Leatt has a very clear hierarchy throughout its ranges too, meaning there is a broad selection of products at different price points. Bib liners are included in this and there are the basic MTB 2.0, the cargo-carrying MTB 3.0, and the MTB 4.0 which are Leatt's best MTB liner shorts and the ones we have on test here. 

Leatt MTB 4.0 Bib Liner

Leatt's bib liner uses a light material that has a comfortable fit  (Image credit: Graham Cottingham)

Design and specifications

Leatt’s top-of-the-range shorts have plenty of features that should see them perform well. The shorts are made from 94 percent Polyamide and six percent Elastane that has loads of stretch while still giving enough support. The deep elasticated cuff has a load of stretch with a grippy silicone treatment on the inside which helps keep them in place without resorting to big silicone grippers. Leatt has added a horizontal fly flap for easy nature breaks too. Unsurprisingly, Leatt has thought of shortening the legs to avoid any impediment of knee pads and the fit is pretty good overall.

As with most shorts, the chamois pad responsibility has been placed in the hands of Elastic Interface. Elastic Interface makes pads for loads of different companies and the pad used in these shorts is a 'Quad-Density “Performance” Chamois' which looks very similar to their MTB Performance 3 pad.

Leatt has equipped their liner with an impressively deep thigh pocket on each leg which they say is specifically for storing a phone. At the back, there is a larger middle pocket that can store a water bottle with two smaller side pockets that have angled openings for easier access. These three pockets sit in front of a fourth larger pocket which is designed to hold a hydration bladder. The bladder pocket has entrances on both sides although there are no guides on the bib straps to manage the hose. It’s BYOB (bring your own bladder) which Leatt sells separately.

Leatt MTB 4.0 Bib Liner

Leatt's rear pockets are reasonably sized but lack security when riding (Image credit: Graham Cottingham)

Performance

Out on the trail, the shorts are comfortable, they don’t have revealing mesh panels like some other bib liners, however, the light material still ventilates well. Not having big mesh panels means the liners have a little more support than the likes of POC’s Air Liner which avoids lots of repositioning mid-ride.

The chamois is fine, it's certainly not the pad I would use for a long day on the trails but I found the chamois had a decent shape and enough padding to last for a good handful of comfortable hours in the saddle.

There is a good reason that Leatt expressly states that the leg pockets are for storing your phone. Leatt’s MTB 4.0 are the only cargo liner I have used that features a silicone gripper around the top of the pockets yet they are also the only liners I have regularly lost items from while riding. Any heavier belongings, like phones. tools, and food, stored in the rear pockets are a likely flight risk so you're going to need to find somewhere else to store them. They are still suitable for small pieces of clothing like gloves although it's probably more convenient to store them in the hip pack or backpack that you will need to carry your phone, tools, and snacks in. The lack of rear security is a huge negative for me, I rely on the rear pockets as I often wear pants when riding so don't have convenient access to the leg pockets. Without dependable rear pockets, it's almost pointless having cargo bibs.

Leatt MTB 4.0 Bib Liner

Leatt uses an Elastic Interface pad with a quick-wicking fabric called ECO X-Tract (Image credit: Graham Cottingham)

Verdict

Leatt’s bib shorts are comfortable and decently ventilated, however, they lack pocket security which severely lets them down. The poor pocket performance makes them hard to recommend over Leatt’s pocketless and cheaper MTB 2.0 shorts, albeit with a sacrifice in chamois comfort. That said, even the MTB 2.0’s are still quite expensive when compared to other bib liner benchmarkers, like Nukeproof’s Blackline Storage.

Leatt appears to be phasing out the MTB 4.0 bib liner too which leaves the MTB 3.0 to take the top spot  As far as we can see the only difference between the two is the MTB 3.0 doesn’t have the hydration bladder pocket at the back, something which most riders won't miss.

Tech specs: Leatt MTB 4.0 bib liner

  • Price: $99.99  / £89.99
  • Materials: 94% Polyamide, 6% Elastane
  • Colors: Black
  • Size availability: XS-XXL
Graham Cottingham
Senior reviews writer, Bike Perfect

Graham Cottingham joined the BikePerfect team as our senior tech writer in 2020. With over 20 years of riding experience, he has dabbled in downhill, enduro, and gravel racing. Not afraid of a challenge, Graham has embraced bikepacking over the last few years and likes nothing more than strapping some bags to his bike and covering big miles to explore Scotland's wildernesses. When he isn’t shredding the gnar in the Tweed Valley, sleeping in bushes, or tinkering with bikes, he is writing tech reviews for BikePerfect.

Rides: Cotic SolarisMax, Stooge MK4, 24 Bicycles Le Toy 3, Surly Steamroller

Height: 177cm

Weight: 71kg

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