The mountain bike cranks we’re talking about here span a price range 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 and slide through a pair of separate bottom bracket bearings. We’ve covered a full range of options from super-light, carbon-armed cross-country race to units tough enough to survive day in day out abuse on downhill courses. That’s why we’ve split the 10 recommended cranks into 3 categories (XC, Trail and Tough).
Our top ten options listed below 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: MEET THE CONTENDERS
At the top end of the pedal turning podium, Race Face smashed their way to pole position in the premium-performance segment with their Next XC and SixC Enduro cranks a few years ago.
They’ve been refining and broadening their black fibre art continually since and the results are still leading the pack. The fourth generation of the Next SL is now even lighter and even stiffer than the original and occasional bonding issues on previous versions seem to have been sorted too.
The new Next R (Rally) has proved deservedly popular among aggressive trail riders who want something slightly tougher without going full SixC. The Cinch splined ring system and universal-fit bottom bracket range make the Race Face portfolio very user friendly, too.
SRAM’s move to ‘DUB’ axle bottom brackets, which are fractionally slimmer than the 30mm standard, was viewed with some scepticism and groans of ‘not another new standard.’ There’s no doubting the new cranks have delivered the goods though. That’s particularly obvious on the completely remodelled XX1 and X01 Eagle cranks which are obviously much stiffer than their flexible forebears. Their mid range Descendant cranks also offer a good balance of performance and weight for those who need to have carbon. The excellent double scoop, triple chain link engagement tooth profile of Xsync2 is now shared across the whole SRAM crank range means everyone gets to benefit from better chain life and a tangibly smoother, more efficient power transfer (at least with a clean chain and ring) too. The GX Eagle crank teams this tech with stiff but impressively light arms to create a really great all rounder for the price.
With bottom bracket heights on bikes getting ever lower, the chance of your crank tips regularly smashing off rocks is increasing with it. Add the fact that the lowest, most central point of your bike is the best place to put weight means metal cranks still make the most sense for most riders.
This toughness is where Shimano really score by still staying away from carbon on their recent refresh of their three top-tier groups. While XTR is certainly heavier than carbon-armed race competition, the HollowTech construction keeps them stiff enough to be used by DH and Enduro riders. XT uses essentially the same cranks with a steel toothed alloy ring while SLX uses a chunkier arm forging and fewer chainring size options to keep price down. It's only 11g heavier than XT though, and as it looks and rides great, it’s definitely a potential challenger for SRAM GX in the cost effectiveness stakes if the chainrings turn out to last. Shimano’s decision to stick with thinner 24mm steel spindles rather than oversized 30mm shafts also allows the use of larger-diameter bearings for increased longevity.
FSA’s Afterburner is another super-tough crankset based around hollow alloy arms. If the avoidance of snapped cranks is foremost when shopping, then weight saving shouldn’t be on your agenda. Then again the hollow arms of DMR’s Axe crank aren’t conspicuously hefty, despite the fact their stiffness is very obvious through your shoes. Several years hammering our long-term set hasn’t bent or dented them, and they’re used by several pro DH riders. Because they’re metal, not carbon fibre, they’re relatively cheap too, making them one of the most impressive all-round DH/Enduro crank we’ve tested.
Hope and Rotor also offer premium alloy alternatives with multi-colour options and adjustable eccentric chainrings as their respective signature features. Flex issues in the Rotor Kapic mean it’s best suited for spinners not stompers, though, and Hope is expensive compared to similar performing, but less fancy-looking cranks.
If you’re wondering where Praxis are in the line-up, we have tested both the Girder Carbon M30 and Cadet M30 cranks extensively and they’re solid, structurally reliable sets. They’re slightly outperformed on price and weight by the other cranks here and durability issues with their unique ‘Wave’ chainrings mean they don’t quite make our recommended list. If you’ve got them on your bike already though, just upgrade the rings with a different brand and you’ve got a fine set-up.
THE BEST MOUNTAIN BIKE CRANKS FOR PRICE
1. SRAM GX Eagle DUB
Super-stiff mid-level option with the hardiness to match
Weight: 624g | Arms: 165mm, 170mm, 175mm | Rings: 32T
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 under foot 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 30-38T 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.
2. Shimano SLX 7100
Shimano’s ‘people’s champion’ crank gets lighter and smarter.
Weight: 631g | Arms: 170mm, 175mm | Rings: 26-36T
Shimano have totally overhauled their top three group sets - XTR, XT and SLX - recently taking them 12-speed and totally changing the design of the chainsets. 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) means more room for bigger bearings which lets you re-use existing Shimano or compatible bottom brackets. SLX (and XT) are available with 28-36 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 tyre 148mm Boost bikes and then 157mm Super Boost bikes) can make choosing confusing, too. You do get a 28 tooth chainring option for twiddling 29ers up steep hills though.
We’ve only just got our hands on a long-term set of SLX 7001 cranks, which means we’ve haven’t had chance to put our usual months of riding into it. While we’re pretty confident that the chunky new arms won’t cause us any structural concerns, we don’t know how that blue finish will hold up cosmetically (not a Shimano strong point previously). The new direct-mount chainring standard is entirely new to us (and everybody else) too, so wear and other potential issues are something we’ll need to track over time.
We’ll be updating all our buyer's guides on a regular basis though, so, if you’re wondering whether SLX is actually as good in real life as first impressions would suggest, then keep checking back for a full review in a few months.
3. FSA Afterburner CK Modular
FSA’s evolved Afterburner is a bombproof bargain
Weight: 704g | Arms: 170mm, 175mm | Rings: 30-34T
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 ‘MegaTooth’ 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 cromoly steel spindle are still the heart of it’s 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.
THE BEST MOUNTAIN BIKE CRANKS FOR RACE
1. Race Face Next SL G4
An outstandingly versatile, podium-light, trail-tough benchmark
Weight: 441g | Arms: 170mm, 175mm | Rings: 24-42T
When Race Face introduced their 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 colour 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 niggle in an otherwise perfect lightweight race/trail product is the lack of a shorter 165mm arm option.
2. SRAM XX1 Eagle DUB SL
Super-light, super-smooth and stiff enough propulsion at a price
Weight: 434g | Arms: 170mm, 175mm | Rings: 30-38T
If we were awarding a prize for 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. Remodelled ‘carbon tuned’ hollow carbon 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 for 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.
3. Rotor Kapic
Lightweight, adjustable orientation oval-ring crank for spinners not stompers
Weight: 547g | Arms: 165mm, 170mm, 175mm | Rings: 28-36T
Rotor have 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 ovalised 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 do their own range of excellent conventional and ceramic bearing bottom brackets but the Kapic will slide into any 30mm bottom bracket you have.
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.
THE BEST MOUNTAIN BIKE CRANKS FOR TRAIL
1. DMR Axe crank and Blade chainring
Super-strong, trail-weight cranks at a decent price
Weight: 661g | Arms: 165mm, 170mm, 175mm | Rings: 26-36T
There’s a high likelihood you’ve never even heard of the crank from dirt jump and general mountain bike misbehaviour legends DMR. This Praxis-produced unit has been our favourite 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 anyway. 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.
2. Truvativ Descendant Carbon DUB
Impressive sweet spot of stiffness, weight, strength and price
Weight: 551g | Arms: 165mm, 170mm, 175mm | Rings: 30-34T
Affordable carbon sounds good, 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.
3. Race Face Next R
Race Face’s Rally crank is XC-light but enduro-strong
Weight: 493g | Arms: 170mm, 175mm | Rings: 24-42T
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’s 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.
4. 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
Like most things Hope lovingly machine into life in their Lancashire factory, the original laser-etched multi-anodised colour 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 pedalling 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’s now got self-extracting hardware so you can remove it trail side if the need arises. The same six-colour, 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 are happy for you to use it for whatever sort of mountain biking you prefer. That said, we’ve only just got a set to play with so we can’t comment on extended durability from our own experience yet. There’s no escaping the fact that Shimano SLX and others compete on basic performance for around half the price either.