Bontrager Flatline MTB shoe review

There are tons of flat-pedal shoe options, but how does Bontrager’s Flatline compare to the competition?

By Guy Kesteven
published
Bontrager Flatline MTB shoe
(Image: © Guy Kesteven)

BikePerfect Verdict

Great grip and feedback for full-gas flat-pedal riding; however, the sizing is generous so try before buying

Pros

  • +

    Super-sticky sole

  • +

    Thin and flexy for feedback

  • +

    Weather-resistant upper

  • +

    Usefully reinforced

Cons

  • -

    Large sizing looseness

  • -

    Overlong laces

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The Bontrager Flatline shoe has been around for a while, and it’s a great maximum grip and feedback alternative to the FiveTen/Adidas monopoly on best MTB flat-pedal shoes. Big sizing can leave you with a free-range fit and silly long laces if you’re not careful, though.

Design and performance

While most MTB flat pedal shoes that we’ve tested with a Vibram sole have been plasticky and low on grip, Bontrager uses the Italian brand’s stickiest MegaGrip rubber. 

Add a shallow EVA-backed sole for just the right amount of flex, and the Flatlines give impressively confident, consistent and communicative connection to your pedals. There’s just enough stiffness to stop them flopping too much under power or flipping a pedal accidentally and low weight gives them a sporty, easy to spin feel when you’re on the gas.  

Wavy tread sections at the toe and heel give a bit more scrambling grip if you’re clambering back up the fast way or you’ve accidentally ended up further down the hill than your bike. There’s textured reinforcement around the upper on the toe and heel too, and the toe box has minimal perforations so it doesn’t flood if it’s splashy. Mid-foot holes mean they don’t often overheat and the tongue and collar are heavily padded for protection.  

Bontrager Flatline MTB shoe

A wave pattern on the toe and heel help with grip when pushing up the trail (Image credit: Guy Kesteven)

Bontrager has flipped its previous ‘tighter-than-most’ fit the other way on the Flatlines though, and super long laces leave loads of flappy excess even if you use the elasticated strap. That means we’d definitely try sizing before you buy if you can, but there is an unconditional 30-day return guarantee if you do need to go smaller.

Verdict

A sticky compound and thin sole mean the Flatline is one of the few shoes able to stick with Five Ten’s legendary Stealth rubber when things get wild. It’s tough, comfortable and reasonably weather-resistant too. Pricing is high though and we’d definitely check sizing to avoid a sloppy fit or excessively flappy laces.

Tech Specs: Bontrager Flatline shoe

  • Price: $129.99 / £124.99
  • Sizes: 39-48
  • Colors: Battleship blue/Marigold (tested), Black
Guy Kesteven
Guy Kesteven
Technical-Editor-at-Large

Guy Kesteven is Bike Perfect's technical editor-at-large. Hatched in Yorkshire he's been hardened by riding round it in all weathers since he was a kid. He spent a few years working in bike shops and warehouses before starting writing and testing for bike mags in 1996. Since then he’s written several million words about several thousand test bikes and a ridiculous amount of riding gear. To make sure he rarely sleeps and to fund his custom tandem habit, he’s also penned a handful of bike-related books and talks to a GoPro for YouTube, too.


Rides: Pace RC295, Cotic FlareMax, Specialized Chisel, Vielo V+1 gravel bike, Nicolai FS Enduro, Landescape custom gravel tandem

Height: 180cm

Weight: 69kg