Skip to main content

Best mountain bike cranks: boost your power on any MTB trail

Jill Kintner rides in Bellingham, Washington
(Image credit: Bryn Atkinson / Red Bull Content Pool)

The best mountain bike cranks on this list span price points from just over $100 to past $500, but they all have a couple of things in common. They’re all single-ring units (although a couple can be configured to twin ring if you want), as that’s become the default choice for trail transmissions.

They all use integrated axles attached to one of the crank arms that slide through a pair of separate bottom bracket bearings. We’ve covered a full range of options from super-light, carbon-armed cross-country cranks to units tough enough to survive day-in-day-out abuse on downhill courses. 

Our top ten best mountain bike cranks are distilled from thrashing around on over 30 different sets of current contenders in a full range of use and weather conditions, plus decades of years on their ancestors, too. That means if a crank is recommended here, it’s been properly hammered to prove it’s one of the best in the world.

Best mountain bike cranks

GX Eagle

(Image credit: SRAM)

SRAM GX Eagle DUB

Super-stiff mid-level option with the hardiness to match

Weight: 624g | Arms: 165mm, 170mm, 175mm | Rings: 32T

Sweet spot of weight, stiffness, strength and cost
Wide range of arm length and replacement ring options
DUB axle won’t fit your existing 30mm bottom bracket

GX Eagle sits in the performance/price sweet spot of SRAM’s extensive crank range. SRAM’s unique X-SYNC 2 ‘double scoop’ chain tooth profile feels smoother and cleaner underfoot than conventional teeth and extends chain life from our anecdotal experience too. It’s also secure over the roughest ground even when worn or dirty and easily replaceable with a wide range of official 30-34T rings, including elliptical and almost indestructible steel or aftermarket chainrings. 

The oversized DUB axle gives universal frame fit and the bearings have proved impressively long-lived in all formats too. The broad, webbed back arms use 7000 series alloy (not 6000 series like most cheaper cranks) to result in a unit that’s proved impressively tough and stiff without adding excess weight. The finish is relatively scrub/scuff proof too. The fact you get a 165mm option for clearance on increasingly common lower bottom bracket height bikes (or shorter legs) is rare in an affordable crank, too.

Shimano SLX 7100

(Image credit: Shimano)

Shimano SLX M7100

Shimano’s ‘people’s champion’ crank gets lighter and smarter

Weight: 631g | Arms: 170mm, 175mm | Rings: 30-34T

Significantly lighter than previous SLX
Shimano’s latest 12 speed tech at a great price
Three different spacing standards make choosing confusing
Totally new design means we’ve got no long term durability data

Shimano's top-three group sets - XTR, XT and SLX - are all 12-speed and have recently undergone a redesign of the chainring. That means SLX potentially looks to be an even better option than before for price-conscious riders. While it looks like it retains an integrated ring and crank arm design, the four-arm ‘spider’ is actually part of a new direct-mount ring system shared across all the new cranks. The new shape, featuring ‘Hollowtech2’ technology, shaves nearly 70g off the previous SLX. That makes it only 11g heavier than XT and a bit of a no-brainer in terms of value. 

The deep arms, chunky spider and 3D-pocket chainrings mean it still feels solid underfoot, too. Sticking with a 24mm steel axle (rather than fatter alloy) so there's more room for bigger bearings, which lets you re-use existing Shimano or compatible bottom brackets. SLX (and XT) is available with 30-34 tooth chainrings, and it’s 12-speed compatible with the same proven narrow-wide tooth profile as before. Both chainsets are available with double chainrings. The only thing you don’t get with SLX (or XT) is a narrower Q-Factor (width between pedals) than 172mm. Three different axle lengths (for standard or fatter tire 148mm Boost bikes and then 157mm Super Boost bikes) can make choosing confusing, too.

If you’re not focused on weight and being able to smash two harder gears at a time, SLX is definitely the most cost-effective workhorse transmission from Shimano’s 12-speed lineup.

FSA Afterburner CK Modular crankset

(Image credit: FSA)

FSA Afterburner CK Modular

FSA’s evolved Afterburner is a bombproof bargain

Weight: 704g | Arms: 170mm, 175mm | Rings: 30-34T

Stiff, strong, cosmetically tough
Wide range of 11-/12-speed rings
Heavy
Rings can be ‘sticky’ at first

FSA’s Afterburner has been around for ages but has never really got the attention it deserves as an absolutely bombproof option. Part of that was due to slightly high pricing and some early tooth profile issues but that’s all been sorted, and the latest (V18) versions are fully 12-speed compatible, too. Hollow forged 6061 alloy arms and a Chromoly steel spindle are still the heart of its strength and stiffness though. 

There’s a massive - 26-38T - range of direct-mount chainring sizes available with different spacer set-ups, allowing you to switch between different frame standards. FSA’s MegaExo bottom brackets generally last well too and come in a full range of frame-compatibility options.

With prices reduced to very reasonable levels, that leaves hefty weight as the only potential issue, but if you tend to punish your cranks, that’s worth sucking up in return for improved longevity.

RaceFace Next SL crank

(Image credit: RaceFace)

RaceFace Next SL G4

An outstandingly versatile, podium-light, trail-tough benchmark

Weight: 441g | Arms: 170mm, 175mm | Rings: 24-42T

Super light yet super stiff and surprisingly tough
Wide range of ring, protector and power meter options
Limited arm length options
Very expensive

When Race Face introduced its full carbon Next SL crank a few years back, it took us a while to believe something so light could be as tough and stiff as it was. There were a few hiccups with bonding and other issues on early versions of the Canadian-made, US carbon construction, but the fourth-generation versions still weigh nothing while taking pretty much everything in their stride.

The Cinch chainrings work and last well, are available in a vast 24-42T range and you can even opt for a double spider if you want. The Cinch axle comes standard in SuperBoost and even fat-bike widths. If you want to measure your watts there’s a retrofit power meter spindle, too. 

Add four color options on the stickers, rubber tip protectors and it looks and lasts as good as it feels under your feet and on the scales. The only gripe in an otherwise perfect lightweight race/trail product is the lack of a shorter 165mm arm option.

SRAM XX1 Eagle DUB SL crankset

(Image credit: SRAM)

SRAM XX1 Eagle DUB SL

Super-light, super-smooth and stiff enough propulsion at a price

Weight: 434g | Arms: 165mm, 170mm, 175mm | Rings: 30-38T

Seriously light but much stiffer than before
Excellent XSync2 tooth technology 
X01 is tougher and not much heavier
Top performance costs top dollar 

If we were awarding a prize for the most improved product, then SRAM’s XX1 DUB chainset would be a definite contender. The top-line XX1 has always been light, but previous versions have been noticeably more flexible than competitors'. Remodeled ‘carbon tuned’ hollow arms and the new DUB axle and bottom bracket design means XX1 (and other SRAM cranks) now feel rock solid underfoot no matter how hard you’re stomping off the start line. 

The double-scoop X-SYNC 2 tooth profile on the direct-mount rings feels smoother and more efficient than standard rings. We’ve been using it long enough to start believing SRAM’s claims that it reduces chain wear, too. 30-38T direct-mount chainring options aren’t as extensive as Race Face but still cater to most users from wattage freaks to low-speed spinners. 

XX1 comes in a 165mm arm length for shorter legs or lower bellied bikes, and DUB bottom brackets are available to fit all bikes. Riders who like rough terrain are probably better off with the slightly heavier but deliberately tougher X01 crank.

Rotor Kapic

(Image credit: Rotor)

Rotor Kapic

Lightweight, adjustable orientation oval-ring crank for spinners not stompers

Weight: 547g | Arms: 165mm, 170mm, 175mm | Rings: 26-34T

Very light for an alloy crank
Lots of ring, ring position and bearing options 
Flexy under peak power
Clearance can be close on fatter chain stays 

Rotor has always been a popular choice with racers due to their potentially power smoothing elliptical chainring tech. The Kapic includes all their signature non-round ring and adjustable orientation features in their lightest format yet. The straight alloy arms hide extensive internal drilling down their lengths plus externally machined grooves to remove excess weight. Both arms then bolt onto a separate 30mm axle, neatly sandwiching the direct-mount QX1 chainring of your choice into place in the process. 

The orientation of the ring can be fine-tuned to modify where it delivers its ovalized power pulse in your pedal stroke - so there's lots to play with. Construction is crisp and immaculate throughout with clear, laser-etched detailing. Rotor does its own range of excellent conventional and ceramic bearing bottom brackets but the Kapic will slide into any 30mm bottom bracket you have, or Boost standard too. 

The straight arms mean a longer axle that needs extensive spacing to clear the frame though. Add the superlight, carved arms and there’s noticeable flex under peak power so Kapic is probably one for spinners, while pedal mashers should look at the chunkier Rex. 

DMR Axe crank and Blade chainring

(Image credit: DMR)

DMR Axe crank and Blade chainring

Super-strong, trail-weight cranks at a decent price

Weight: 661g | Arms: 165mm, 170mm, 175mm | Rings: 26-36T

Impressively tough yet lightweight hammer crank
Decent size and ring range sold separately
Only works with Praxis bottom brackets
Can be too stiff on really long descents

There’s a high likelihood you’ve never even heard of the crank from dirt jump and general mountain bike legends DMR. This Praxis-produced unit has been our favorite fail-safe option for left-field builds for several years though, and every set we’ve used is still going strong. 

The big arms and oversized axle immediately feel stiffer than most set-ups through the pedals so it’s no surprise they’re used by several top DH riders. They give tons of traction feedback and torque transfer too, although those with sensitive soles might start suffering on long, rocky descents. They also come in shorter 165mm lengths for the latest enduro bikes.

The ‘Blade’ chainrings are available separately in a wide range of sizes, but the three-bolt pattern means you can fit any SRAM-compatible rings you want. The 30/28mm spindle and M30 Praxis bottom-bracket compatibility are a giveaway on origin and can present a spares problem if you don’t plan ahead. The Praxis bearings are decent though and they fit any sort of bike (the Press Fit version is particularly clever) so it’s unlikely to be an issue in normal use.

Truvativ Descendant Carbon DUB crankset

(Image credit: Truvativ)

Truvativ Descendant Carbon DUB

Impressive sweet spot of stiffness, weight, strength and price

Weight: 551g | Arms: 165mm, 170mm, 175mm | Rings: 30-34T

Light enough for XC, tough enough for enduro
X-SYNC 2 rings are stand out performers  
Carbon won’t suit regular trail tappers
Only works with DUB bottom brackets  

Affordable carbon sounds good and can often be pretty, but it’s rarely the greatest in terms of performance. That makes Truvativ’s great mix of price and purpose even more impressive. The slightly tapered carbon and alloy arms and ‘almost-30mm-but-not-quite-compatible’ DUB axle keep weight usefully low. 

They still feel much stiffer in use than an alloy crank of similar weight and price though, and we’ve properly punished several sets without any problem. They’re cosmetically tougher than most alloy cranks as well, and rubber-protectors are available if you find yourself scuffing the ends on rocks.

While they only work with SRAM DUB bottom brackets, it’s not really an issue as they’re available in a format to fit any bike, and they’ve proved decently durable over the past year of testing. The X-SYNC 2 rings, with their distinctive double-scoop tooth profile, spread engagement and wear to produce smoother power as well as preserve chains. They’re available in tons of sizes.

Race Face Next R crankset

(Image credit: Race Face)

Race Face Next Rally

Race Face’s Next Rally crank is XC-light but enduro-strong

Weight: 495g | Arms: 170mm, 175mm | Rings: 24-42T

Lighter than a lot of XC cranks but still seriously tough
Wide range of ring, protector and power meter options
No 165mm option for short legs or low bikes
Go SixC if you want DH level strength

If you’re slightly concerned about trusting the Next SL crank, or just want purple and green logo options on a properly tough unit that still comes in under 500g, the Next Rally is where it’s at. The same made-in-Canada, US-sourced carbon construction as the Next SL is beefed up with the pedal insert from Race Face’s SixC cranks to spread impact and landing loads. 

The bolt-in Cinch axle system adds easy spindle replacement if you really slam them (we’ve never managed it) and width options up to fat bike. There’s even a neat, totally protected power-meter option.

There are tons of direct-mount chainring options too, which leaves the lack of a 165mm option for short legs and low bikes as the only glitch in the Rally matrix. Otherwise, if you’re looking for something that’ll hack a lot of mass out of your bikes but still feel super stiff underfoot and survive Enduro-style abuse, then this is literally Next level if you can afford it.

Hope Evo crankset

(Image credit: Hope)

Hope Evo

It’s early days but EVO is definitely a significant improvement for Hope cranks

Weight: 565g | Arms: 165mm, 170mm, 175mm | Rings: 26-36T

Lighter and stiffer than Hope’s original cranks
Excellent BB system is now more user friendly than before
Exquisite UK workmanship comes at a cost

Like most things Hope lovingly machines into life in its Lancashire factory, the original laser-etched multi-anodized color option cranks were an instant hit with their legion of loyal fans. They have proved just as tough as Hope's venerable bottom brackets.

Compared with lighter, cheaper alloy cranks they were noticeably flexy when pedaling or cornering hard and the unique tools needed for fit and removal made trail-side maintenance a pain.

Thankfully the new EVO cranks are the result of intense stress-analysis scrutiny to deliver a crank that’s 15 per cent lighter and stiffer than the original. It now has self-extracting hardware so you can remove it trailside if the need arises. The same six-color, direct-mount, single or double spider and axle widths from old-school to fat-bike options are also available. Hope’s rings are particularly tough, with extra motorcross-style scoops for squeezing mud out of the mix, too. 

As it’s been extensively pre-tested by Pro DH rider Adam ‘Gas to flat’ Brayton, Hope is happy for you to use it for whatever sort of mountain biking you prefer. However, there’s no escaping the fact that Shimano SLX and others compete on basic performance for around half the price.

Best mountain bike cranks: what to know before you buy 

1. 1x or 2x? 

All of the best mountain bike cranks listed here are 1x drivetrain systems. That means that there's only one cog or gear on the front of the bike. This is quickly becoming an industry standard, even on cheaper, budget mountain bikes. You should keep in mind that 2x systems still exist. These drivetrain systems make shifting and maintenance more complicated. Our prediction is that 2x drivetrain systems will be relegated to the history books very soon. 

2. Sizing 

There are a couple of sizing measurements to keep in mind when looking for the best mountain bike cranks. First, there is the size of the crank arm. Crank arm size can impact riding style and bike fit, however, most riders just run what has come pre-installed on their bike. It's good to keep in mind that longer crank arms run the risk of striking rocks and trail debris with your pedal or crank arm. This rarely damages the parts to the point of disrepair, however, it is not a pleasant experience and can lead to crashes. 

3. Chainring size and compatibility 

You'll also want to check that the crank arm is compatible with your desired chainring model or brand. Most cranks are compatible with most chainrings, so you won't have to go searching too far when looking to replace a worn-down chainring or swap out for a different amount of teeth. 

Guy Kesteven
Guy has been riding mountain bikes since before they were mountain bikes and is right handy on an offroad tandem (of course he is).