The mountain bike suspension fork is a vital piece of equipment as it smooths out the trail surface by absorbing impacts and imperfections, subsequently improving traction, pliancy, speed and control over bumpy and gnarly terrain.
However, this wasn’t always the case. Early examples of the mountain bike were bereft of such comfort-providing contraptions and rigid frames were the order of the day. In fact it wasn’t until the early 1990s that the suspension fork was introduced to both downhill and cross-country racing. While it radically altered the feel and performance of the bikes, these early examples were more of the one-size-fits-all variety and sported between 30-50mm of travel.
Owing to the fact that the sport now spans myriad disciplines - cross-country, trail/all mountain, enduro and downhill - the best mountain bike suspension forks have become more specialised in application and function. As a result, each mountain bike discipline places a very different set of demands on the bike and rider so the modern suspension fork varies in terms of travel, spring systems and stanchion thickness.
Nowadays, suspension forks are lighter than ever before, can be infinitely tuned and fettled, have increased amount of suspension travel and improved feedback. Which fork is best for your particular setup depends largely on the type of riding/discipline you prefer.
Best mountain bike forks: what you need to know
The modern mountain bike suspension fork is a complicated piece of kit and naturally comprises many moving parts. It’s worth familiarising yourself with the fork’s anatomy and the various terms associated with it before making your choice.
Modern mountain bike geometries are specifically designed around suspension travel. For example, cross-country mountain bikes feature short-travel forks as the trails are relatively smooth, comprise lots of climbing and need to be light/responsive while still providing a decent range of compression. As you move through the various types of mountain biking, the weight, stanchion thickness and travel all increase so as to meet the demanding needs of each discipline.
- Cross-country: 100-120mm travel, 30-32mm stanchion diameter
- Trail: 120-150mm travel, 34mm stanchion diameter
- Enduro: 150-180mm travel, 35-38mm stanchion diameter
- Downhill: 180-200mm travel, 40mm stanchion diameter
The diameter of the stanchion tubes directly affects the fork’s lateral stiffness. The secret here is finding a balance between weight and performance, as wider stanchions are stiffer and heavier than their narrower counterparts but are more resilient to greater impacts from rough terrain and jump landings.
Thru-axles are wider, stronger and stiffer than the old quick-release skewer systems of yesteryear and have been the gold standard on most high-end performance mountain bikes for sometime now. The 20mm standard is generally reserved for downhill and enduro while the 15mm thru-axle is found on just about all trail and cross-country bikes.
Until Boost hub spacing came along, the standard for thru-axles was 100mm spacing in the front (110mm for downhill bikes) and 135mm/142mm spacing in the rear. The wider hub and flange spacing offered by Boost has increased the stiffness of 29-inch and 650b wheels even further with the new standards coming in at 110mm (front) and 148mm (rear).
There are two steerer types - straight and tapered. A standard steerer tube is straight with a 1-1/8-inch diameter and is associated more with downhill mountain biking. Most modern forks come standard with tapered steerers as they’re stiffer, lighter and provide better feel and response than a regular straight steerer.
Volume spacers or tokens allow you to fine tune the air volume of your fork. Adding tokens reduces the volume of the air chamber causing the air pressure to ramp up quickly so the spring pressure can be set low, allowing more suspension sag without the risk of bottoming out. Removing tokens will provide the reverse effect.
There are two different spring systems: air and coil springs. Air springs have become the staple choice on modern suspension forks as they are tuneable and have a progressive compression rate — the feel is softer in the first part of the travel and then gets stiffer as more compression is applied. Coil springs on the other hand are found predominantly on downhill bikes. Linear in feel, they provides consistent impact absorption over the range of spring travel.
Scroll down to see BikePerfect's roundup of the best mountain bike suspension forks available to buy for 2020.
The best XC (cross country) mountain bike forks
Fox Float 32 Factory Step-Cast
A plush and performance-focused fork for the gram counters
Weight: 1387g (29er) | Travel: 100mm | Stanchion diameter: 32mm | Spring system: Air, FIT4 damper | Material: Magnesium and forged aluminium | Wheel size: 650B, 29er | Steerer: Tapered | Axle: 15x110mm Boost, 15x100mm
If it’s a high-performance, lightweight cross-country suspension fork that you’re after, there aren’t many options that can beat the Fox Float 32 Factory Step-Cast.
Compared to many of its Boost-equipped rivals, the Fox 32 is appreciably narrower when measured from leg to leg thanks to a stepped cut-out at the drop-outs. This nifty feature has not only improved lateral stiffness but considerably reduced its weight over its rivals, too.
For 2020, Fox has redesigned the crown and claim improved stiffness of 20%, something that if true will made the 32 as stiff as the current 34 fork, its bigger, trail-focussed cousin.
RockShox SID Ultimate Carbon
Bombproof suspension fork with the pedigree and featherweight performance to match
Weight: 1481g (650B) | Travel: 100mm | Stanchion diameter: 32mm | Spring system: Air, Charger 2 RLC damper | Material: Carbon, magnesium and forged aluminium | Wheel size: 650B, 29er | Steerer: Tapered | Axle: 15x110mm, Boost
The RockShox SID Ultimate Carbon sits at the very top of the company’s cross-country range of suspension forks and forms part of the ‘Signature Series’. At 1481g, it may represent the lightest model in the range but it’s still a fair whack heavier than its chief adversary, the Fox Float 32 Factory Step-Cast.
Despite this, however, the SID is appreciably stiff and can be punished day in, day out without the fear of something going wrong. The Charger 2 RLC damper system is highly tuneable and delivers coil-spring-like levels of linear progression and feel.
Available in the choice of SID Blue or Gloss Black it can be matched to any modern bicycle colour-way, ensuring you stand out on the trail.
The best trail mountain bike forks
RockShox Yari RC
An easy-to-set-up, no-nonsense suspension fork designed for hard riding and abuse
Weight: 2046g (29er) | Travel: 150mm | Stanchion diameter: 35mm | Spring system: Air, Motion Control damper | Material: Magnesium and forged aluminium | Wheel size: 650B, 29er | Steerer: Tapered | Axle: 15x110mm, Boost
While the RockShox Yari shares its DNA with the Lyrik, including its chassis, travel options, offsets and 35mm stanchion structure, it differs by way of its damper system — Motion Control vs the Lyrik’s Charger 2.1 RC2 damper.
Sure, this means it is a little less refined in terms of performance and damping plushness but the Yari is a reliable and robust performer designed to be ridden hard thanks to the stiff chassis and ease with which it can be set up.
If you’re looking for a big-hitting, affordable fork with the pedigree to match it’s hard to find anything as reliable as the Yari.
Cane Creek Helm Air
Robust and stiff, the Cane Creek Helm Air provides next-level adjustability and tuning options for the purist
Weight: 2080g (29er) | Travel: 100mm-160mm | Stanchion diameter: 35mm | Spring system: Air | Material: Magnesium and forged aluminium | Wheel size: 650B, 29er | Steerer: Tapered | Axle: 15x110mm, Boost
A stiff and stocky-looking fork, the Cane Creek Helm Air boasts 35mm stanchions, a tapered steerer and internally adjustable travel from 100-160 mm.
A mono-tube damper with high/low-speed compression and rebound adjustments control the fork’s movement and sensitivity bias. One of the Helm’s drawcards is undoubtedly the configurable negative air spring that allows riders to tailor the individual pressures for the positive and negative air chambers.
The Helm also benefits from a unique axle system called D-LOC. Apart from keeping the wheel in place, the D-LOC axle thwarts rotational and torsional loads to the upper bushings during cornering and high-speed compression.
Fox Float 34 Factory
A light, mid-travel fork option with tuneable, buttery-smooth performance
Weight: 1770g (650B) | Travel: 120mm-150mm | Stanchion diameter: 34mm, Kashima | Spring system: Air (Evol float), FIT4 damper | Material: Magnesium and forged aluminium | Wheel size: 650B, 29er | Steerer: Tapered | Axle: 15x110mm, Boost
Designed for aggressive trail riders, the Fox Float 34 Factory uses a three-position FIT4 damper and super lightweight chassis — 1770g in 650b guise, which is incredibly light.
As the name references, it gets 34mm stanchions complete with envy-inducing gold Kashima coatings, which are claimed to increases shock smoothness and sensitivity.
Despite its low weight, the Fox 34 is stiff, offering the suppleness and plush damping quality expected from Fox. Two fork options are available: 650b which provides between 140mm and 150mm travel, while the 29er fork can be optioned in travel ranging from 120-140mm.
The best enduro mountain bike forks
RockShox Lyrik RC2
The most complete enduro fork on the market
Weight: 2032g (29er) | Travel: 180mm | Stanchion diameter: 35mm | Spring system: Air, Charger 2 RC2 damper | Material: Magnesium and forged aluminium | Wheel size: 650B, 29er | Steerer: Tapered | Axle: 15x110mm, Boost
Bold and expressive, the RockShox Lyrik RC2 was recently updated - both visually and internally - to better cope with the rigours of enduro racing.
As such, the Lyrik gains a fresh lick of red paint which contrasts the black uppers quite superbly - however, it's under the skin where the biggest updates have been implemented.
The air spring shaft is now hollowed out, which boasts 42% more negative spring volume than before (claim RockShox) resulting in better small-bump sensitivity and coil-spring-like linearity.
The updated Charger 2 RC2 damper has eschewed the three-position lever (this means no lockout) of its forebear in favour of a high-speed, five-click adjuster that is claimed to be more tuneable and responsive to trail nuances.
Manitou Mattoc Pro
Reliable and adjustable, the Manitou Mattoc Pro is one of the best entry-level options around
Weight: 2033g (29er) | Travel: 160mm (adjustable 140-170mm) | Stanchion diameter: 34mm | Spring system: Dorado Air | Material: Magnesium and forged aluminium | Wheel size: 650B, 29er | Steerer: Tapered | Axle: 15x110mm, Boost
The Manitou name is renowned for reliability, affordability and performance and while it’s lived in the shadows of more illustrious players for many years, the new Mattoc Pro is hoping to change perceptions for good.
Stealth in appearance, the Mattoc Pro employs smaller stanchions to other 160mm forks - in this, case 34mm vs the Lyrik’s 35mm and Bomber’s 36mm. Available in travel options ranging from 140mm-170mm at 10mm increments and three crown offsets of 44mm, 48mm and 51mm, the Mattoc is compatible with 650b, 650b+/29er and 29er+ geometries.
It’s not as tuneable as some of its rivals but the Manitou Mattoc Pro does offer some degree of adjustability around high- and low-speed compression. It’s simple in application and makes no bones about its job - soak up the bumps and provide high levels of traction.
Marzocchi Bomber Z1
A durable, affordable enduro fork that has been designed to take a beating on the trail
Weight: 2251g (650B) | Travel: 150-180mm (650b) | Stanchion diameter: 36mm | Spring system: Air, (Evol float) FIT Grip damper | Material: Magnesium and forged aluminium | Wheel size: 650B, 29er | Steerer: Tapered | Axle: 15x110mm, Boost
The Marzocchi Bomber Z1 is back - well, sort of, thanks to Fox Racing who now owns the iconic fork maker. Air-sprung in application, the Bomber is aimed at riders looking for a long-travel option capable of dismissing tricky and demanding trails with ease. It’s an appreciably durable fork.
Not surprisingly, the new Bomber benefits from trickle-down technology from Fox, employing such additions as an EVOL air spring and a FIT GRIP damper as well as the same crown and steerer from the Fox Rhythm.
The Bomber Z1’s 36mm chassis is constructed from 6000 Series aluminium and is available in both 29er/650b options with travel ranging from 150mm to 180mm. The air spring curve is tuneable through volume spacers.
The best downhill mountain bike forks
Fox Float 40 Factory
The Fox Float 40 Factory is still the champion’s champion
Weight: 2780g (26er) | Travel: 203mm | Stanchion diameter: 40mm, Kashima | Spring system: Air, FIT GRIP2 damper | Material: Magnesium and forged aluminium | Wheel size: 650B, 29er | Steerer: Straight | Axle: 20x110mm, Boost
Fox’s venerable Float 40 Factory fork needs no introduction having experienced prodigious success at World Cup level over the past several years.
Built around 40mm stanchions and featuring a whopping 203mm of travel, the fork is naturally very stiff and responsive, if anything a touch on the heavy side despite weight-saving measures around the crown and lowers.
The large volume of the air chamber means the 40 has a linear stroke, tuneable by way of volume tokens which deliver a compression stroke as plush as any of Fox’s Factory Kashima-coated forks.
Further adjustably can be made by fiddling with the four-way GRIP2 damper that independently adjusts high- and low-speed compression and rebound.
RockShox Boxxer Ultimate
Forgiving and highly tuneable, the RockShox Boxxer adds compliancy and confidence to the demanding terrain of downhill racing
Weight: 2565g (650B) | Travel: 200mm | Stanchion diameter: 35mm, Kashima | Spring system: Air, Charger 2.1 RC2 | Material: Magnesium and forged aluminium | Wheel size: 650B, 29er | Steerer: Straight | Axle: 20x110mm, Boost
As far as heavy-hitting downhill suspension forks go, the Rock Shox Boxxer has been a favourite in the pro rungs for years now. The latest version, the Boxxer Ultimate, has received several tweaks including updated seals and oil, and a Charger 2.1 damper system claimed to make it run smoother than before.
Furthermore, this new damper system allows the fork to stay higher in the travel, compress more linearly (like a coil spring) and rebound with more control for better landings.
A big difference between the Boxxer and its rivals has always been the 35mm stanchion tubing, which is notably slimmer than its 40mm rivals. While this does add some torsional twist, the Boxxer never feels unsettled - instead, it provides pliancy and confidence in spades.