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Best mountain bike suspension forks 2024 | Top-rated MTB forks and buyer's guide

Plus our buyer's guide to MTB forks

Steve Behr

Published: December 8, 2023 at 4:00 pm

Looking for the best mountain bike suspension fork? You've come to the right place.

Buying a new suspension fork for your mountain bike is one of the priciest – and potentially most effective – upgrades you can make to your mountain bike. Even when buying a complete bike, the fork it comes with is a serious consideration.

You’ll want either a suspension fork that irons out the harshest of trail feedback, helping your hands to last longer whatever bike you ride, or you’ll want the fork to sit smoothly into the first part of its travel to keep your front wheel stuck to the ground.

You’ll also need enough stiffness to provide accurate and predictable steering, and enough adjustability to fine-tune the fork to your needs, but not so much that it’s a nightmare to set up.

You'll probably want it to be as light as possible too, and hopefully not cost the earth.

We’ve tested forks to suit a broad range of budgets, making sure to include some top-shelf options because these are what people tend to buy as an upgrade to their bike.

You can read our full mountain bike suspension forks buyer's guide at the end of this article.

Best mountain bike suspension forks of 2024

RockShox SID Ultimate 3P

2024 RockShox SID Ultimate 3P fork (with TwistLoc remote)
The new RockShox SID Ultimate 3P impresses with supple and capable ride characteristics. - Andy Lloyd / Our Media
  • Price: £1,069/$999/€1,199 as tested
  • Wheel size/travel options: 110mm and 120mm (29in), 120mm tested
  • Weight: 1,600g (29in x 120mm)
  • Pros: Initially very sensitive; remains controlled in rough terrain
  • Cons: TwistLoc remote grips don't have lock-on option

The SID Ultimate 3P is the latest top-level cross-country fork from RockShox, offering a more refined and capable ride feel than the fork it replaced.

Its new Charger Race Day 2 damper gives the fork three positions, which can be switched between ‘open’, ‘pedal’ and ‘lock’ modes via the crown-top lever or optional TwistLoc remote (£119/$117/€133).

We found 'open' and 'pedal' to be our most frequented modes, rarely using the 'lock' mode unless slugging up road ascents and the odd fireroad.

The SID Ultimate 3P is keen to sink into the first few millimetres of travel without hesitation, making for a supple ride with a smooth, ground-hugging feel over small bumps.

Its mid-stroke support builds progressively, with the ramp-up near the end of the travel remaining calm on big hits.

The new 35mm chassis enables the fork to attack fast, technical descents with precision, with only some flex being detected on steeper turns with fast catch berms that would challenge most trail forks.

Fox 36 Factory GRIP2

Fox 36 Factory GRIP2 suspension fork
The Fox 36 Factory GRIP2 is a tremendously capable fork. - Steve Behr
  • Price: £1,139 as tested
  • Wheel size/travel options: 27.5in with 160, 170, 180mm; 29in with 160 (tested), 170mm
  • Weight: 2,091g (29in x 160mm)
  • Pros: Impressively supple and composed over high-frequency chatter
  • Cons: Firm high-speed compression damping when set to open

The all-singing Fox 36 GRIP2 Factory is one of the most expensive forks we’ve tested. Fortunately, it’s got performance to match.

Its four-way adjustable damper has high- and low-speed adjustment for both compression and rebound damping. Fortunately, Fox nailed the setup guide, so it’s one of the easiest forks to get in the right ballpark despite the vast range of adjustments.

It’s also one of the best performers, particularly over big holes and choppy unpredictable ground. The independent high-speed rebound adjustment seems to make it more controlled and calm when returning from deep in the stroke if, like us, you’re running a lot of pressure in the spring.

It’s not quite as sensitive off the top of the stroke as its rival, the RockShox Lyrik, though, so there isn’t quite as much traction in low-load situations.

While very active and supple over small bumps, it’s a little stingy with its travel over bigger impacts, even with the compression damping fully open. This isn’t necessarily a bad thing, but we would have liked the ability to run the high-speed compression a little more open for long-run comfort.

There were situations where the 36 was the best fork we’ve ever used.

Manitou Mattoc Pro

Manitou Mattoc Pro suspension mountain bike fork
Manitou's new top-line trail fork, the Mattoc Pro. - Andy Lloyd / Our Media
  • Price: £1,323 / $1,050 / €1,260 as tested
  • Wheel size/travel options: 27.5in with 120, 140mm; 29in with 120, 140mm (tested)
  • Weight: 1,797g (29in x 140mm)
  • Pros: Lovely feel through travel; easily adjustable; competitive weight
  • Cons: Air valve access could be easier; Hexlock axle isn’t quite as intuitive as competitors

The Mattoc Pro impressed us with its impeccable suppleness and great end-of-stroke control.

Manitou has given the fork plenty of adjustment with an MC2 damper, with hydraulic bottom-out in the stanchion offering high and low-speed compression and single rebound adjustment.

All this tech pays dividends, with the Mattoc Pro offering plenty of grip and comfort, with ample control late into the stroke and plenty of usable adjustment.

The Hexlock axle is more difficult to use than other securing axles, with a hand needed to balance the bike, push the axle and turn the Allen key from the other side of the fork.

We also found the air valve to be in an awkward position at the bottom of the fork, making it difficult to use with some shock pumps.

Manitou Mezzer Pro

Manitou Mezzer mountain bike suspension fork
The fork's performance really impressed our tester. - Alex Evans
  • Price: £899.99/$999.99/€1,050 as tested
  • Wheelsize/travel options: 27.5in and 29in (tested), both adjustable between 140 and 180mm in 10mm increments (160mm tested)
  • Weight: 2,093g (29in x 160mm)
  • Pros: Very supple with great mid- and end-stroke support
  • Cons: Difficult to set up

The Mezzer is a surprise performer, offering an excellent balance between small-bump sensitivity and bottom-out resistance. It’s particularly capable no matter how deep into its travel you go or how hard you push it.

The chassis also hits the perfect balance of control, accuracy and compliance, feeling stiff when it needs to – such as under corners – but didn’t cause our front wheel to bounce or judder offline, also helping to reduce hand fatigue.

The MC2 damper’s high-speed compression is light enough to absorb fast impacts and proved to be incredibly supple. Its low-speed damping gives plenty of support through turns and compressions, adding to the capabilities of the impressive air spring.

Although the air spring is quite hard to set up – and you need to follow the supplied guide exactly – once you get it right, the performance that’s unlocked is virtually unparalleled on the trail.

If you’re looking to upgrade your fork and were considering a RockShox Lyrik or Fox 36 GRIP2, the Mezzer has to be on your shortlist as well.

The Manitou Mezzer wasn’t tested as a part of our latest fork group test, and doesn’t feature in our video, but was tested and rated to the same criteria, and performed exceptionally well.

Marzocchi Bomber Z1

Suspension fork for mountain bike
Marzocchi's Bomber Z1. - Steve Behr
  • Price: £749 as tested
  • Wheel size/travel options: 27.5in with 130, 140, 150, 160, 170mm; 29in with 150, 160 (tested), 170, 180mm
  • Weight: 2,249g (29in x 160mm)
  • Pros: Comfortable with big-hit capabilities
  • Cons: Firm at the beginning of the stroke; heavy

Marzocchi is now a sister brand of Fox, and the Z1 shares a lot of features with the Fox 36. However, it's designed to hit a lower price point.

Because it uses a lower-grade aluminium in the upper tubes, it’s one of the heaviest enduro forks around at 2,249g, but the extra weight is not noticeable on the trail.

The air-sprung Z1 isn’t as soft at the very start of its travel as the Fox 36, or the Yari and Lyrik, so it needs a lower air pressure to get it to sag properly, along with a healthy stack of volume spacers to stop it using all of its travel too easily.

It still canters through the middle of its travel a bit more easily than those other forks too, making it feel a little less predictable and refined. The flipside is it swallows kerb-sized rocks like a champ, which means good long-run comfort.

The key comparison is to the RockShox Yari (below). The Z1 is more willing to swallow large impacts, making it more forgiving in those big-hit scenarios, but the Yari is more supple at the start of the stroke, and offers more traction and more predictable support. It’s a touch lighter and cheaper too.

On balance, the Yari just edges it for us. But if big-hit capability is your priority, and you can’t stretch to the RockShox Lyrik or Fox 36, the Z1 is a good option.

Öhlins RXF38 m.2

Ohlins RXF 38 m.2 mountain bike suspension fork
The RXF38 m.2 is available in one model only. - Ian Linton / Our Media
  • Price: £1,45/$1,450 as tested
  • Wheel size/travel options: 160-180mm (29in), 170mm tested
  • Weight: 2,354g (29in x 170mm)
  • Pros: Smooth and fluttery off-the-top; tunable bottom-out
  • Cons: Rebound damping re-tune might be needed

The RXF38 has impressive off-the-top sensitivity, minimising trail chatter and providing huge amounts of comfort and grip.

Mid-size hits such as brake bumps are catered for with buckets of support. The damper controls the impacts with a calmness that enables you to focus on what's down the trail rather than beneath your front wheel, leading to more speed.

The fork handled compressions well, never once diving under hard braking, which gave confidence to weight the front wheel into catch berms and steep sections of trail.

The rebound damping on our test fork was a little hard, which may be a problem for lighter riders, but the brand offers various tunes, so finding the right one shouldn't be hard.

It was also a difficult fork to set up, with a negative spring volume-reducer spacer installed in the fork from the factory that wasn't mentioned in the manual.

RockShox BoXXer Ultimate

RockShox BoXXer Ultimate
The BoXXer Ultimate delivers confidence-inspiring performance that balances suppleness and support - Anthony Smith
  • Price: £2,029/$1,899/€2,279 / AU$3,265 as tested
  • Wheel size/travel options: 200mm (27.5in and 29in)
  • Weight: 2,840g (29in x 200mm) Claimed
  • Pros: New chassis gives precise handling, DebonAir twin tube spring gives plenty of support without a firm spike or ramp-up deep in the travel
  • Cons: Rebound dial stiff and creaky

The RockShox BoXXer Ultimate receives 38mm stanchions in its current guise which adds plenty of accuracy and makes the fork hold a line well, even when traversing slippery rocks after poor line choices.

A smooth and quite ride quality calms the front of the bike and makes the BoXXer feel reassuringly predictable, while the break away force of is minimal, with the fork sliding easily into its initial stoke.

The beginning of the stroke takes the sting out of small high frequency bumps impressively well, isolating your hands without losing support.

Charging through rough sections reveals how composed this fork is, with the mid-stroke soaking up big hits while delivering plenty of support to push against.

There's no harsh ramp-up or firmness present at the end of stroke, making big drops and high speed compressions reassuringly composed as the linear nature of the fork feels like it's only using the travel it needs.

After some use, the rebound dial on our early test model became stiff and creaky, but this didn't hinder performance.

RockShox Lyrik Ultimate

RockShox fork 2023
The Lyrik's new 35mm chassis retains characterful stiffness and flex. - Mick Kirkman / Our Media
  • Price: £1,013/$1,049/€1,134 as tested
  • Wheel size/travel options: 150-160mm (27.5in and 29in), 160mm tested
  • Weight: 2,042g (29in x 160mm)
  • Pros: Unrivalled mid-stroke damper support; feature-laden additions improve performance
  • Cons: Small-bump sensitivity not perfect

The RockShox Lyrik Ultimate sets a benchmark for support and height control with its Charger 3 damper and DebonAir spring at the sacrifice of small-bump sensitivity.

The damper enables you to confidently weight the front wheel while hammering it into gnarly sections of trail without fear of the fork diving under braking.

The DebonAir handles lower spring pressures with impressively supple and effective ramp-up that was helped by the damper to not blow through its travel on big hits.

Small-bump performance is the only letdown. While the ButterCups mute harsher bumps, the fork remains almost static on small jagged rock paths found at trail centres.

RockShox Yari RC Debonair

Suspension fork for mountain bike
The RockShox Yari RC Debonair shares a 35mm chassis with the Lyrik. - Steve Behr
  • Prize: £695/AU$1,200 as tested
  • Wheel size/travel options: 150mm, 160mm (tested), 170mm and 180mm travel for 27.5in and 29in wheels
  • Weight: 2,129g (29in x 160mm)
  • Pros: Great off-the-top sensitivity
  • Cons: Motion Control damper lacks low-speed support and is occasionally harsh over big impacts

The RockShox Yari uses the same stiff 35mm chassis as its pricier sibling, the Lyrik. It now gets the same supple, class-leading Debonair spring too.

The difference is in the damper. The Yari’s more simple Motion Control unit doesn’t provide the same digressive damping – blending low-speed support with high-speed suppleness – that you get from the Lyrik’s Charger.

As a result, it doesn’t feel quite as settled and supportive when braking, and occasionally spikes when slapping down to earth with a thud.

Realistically, though, it’s rare that the less refined damper lets the side down, and this is compared to the best mountain bike forks.

The Yari offers better long-run comfort and small-bump traction than almost anything else on the market, including forks costing several hundred pounds more.

If the slightly unrefined damper bothers you, you can always upgrade it to a Lyrik spec further down the road.

RockShox ZEB Ultimate

RockShox ZEB Ultimate fork - mountain bike suspension fork
Mick Kirkman / Our Media
  • Price: £1,119/$1,253/€1,159 as tested
  • Wheel size/travel options: 150-190mm (27.5in and 29in)
  • Pros: Easy to make meaningful adjustments; good mid-stroke support
  • Cons: Lighter riders may need a re-tune

RockShox's ZEB Ultimate is one of the best forks on offer, with seriously impressive composure and control on rough trails.

Aimed at enduro racers, the ZEB Ultimate has best-in-class small-bump sensitivity with a supple and silent feel that does a great job of tracking trail imperfections,

There is plenty of support deeper into the travel, delivering a calm and composed ride through steep gnarly sections where your weight is over the front of the bike.

Its progression is very gradual through the entire stroke, giving confidence towards the end, where other forks can feel harsh.

The dials enable high levels of adjustment, with high- and low-speed compression all tuneable from the crown of the fork.

We found our test tune to not compliment lighter riders, with all adjustments needing to be fully open for the desired fork setup, reducing overall tunability

Cane Creek Helm MKII

Cane Creek Helm MKII - Enduro suspension fork
Andy Lloyd / Our Media
  • Price: £1,100/$1,100/AU$1645 as tested
  • Wheel size/travel options: 130-160mm (29in and 650b), 160mm tested
  • Weight: 2.08kg (29in)
  • Pros: High levels of adjustability; supple ride feel
  • Cons: Not the most supportive in the mid-range

The Helm MKII has 35mm stanchions, which felt accurate through rocky sections with no significant flex or binding.

You get external low- and high-speed compression and low-speed rebound-damping adjustment.

The negative air spring is equalised manually from the positive spring, making it easy to tune the fork's progression. It takes a little figuring out to set up the fork, but once you get it dialled in, it’s an impressive piece of kit.

The Helm MKII is wonderfully supple through the initial part of its travel, so takes a lot of the sting and buzz out of the trails.

Deeper into the mid-stroke, it feels as though it relies on its spring for support more than its damping, which makes for a very plush ride.

It doesn’t have the most supportive mid-stroke, but there’s a decent range of low-speed compression damping should you want to wind some on. Bigger hits are dealt with comfortably, too.

Whether you’re hitting heavy compressions or landing massive drops, the Helm MKII’s progression builds consistently throughout its travel, which makes for a predictable-feeling ride.

Cane Creek Helm MKII Coil

Cane Creek Helm MKII mountain bike suspension fork
At £1,049.99/$1,049.99, it's not the most expensive fork. - Alex Evans
  • Price: £1,049.99/$1,049.99 as tested
  • Wheel size/travel options: 130-160mm, 29in and 27.5in
  • Weight: 2,330g (29in x 160mm)
  • Pros: Supremely supple; easy to adjust, good bottom-out resistance
  • Cons: Could be overdamped for lighter riders; tyre clearance

Cane Creek's Helm MKII Coil impresses with its suppleness, ironing out small-bump chatter and isolating your hands from well-worn trails.

With four spring options to choose from for riders weighing 45 to 100kg, we found the suggested spring to be too soft, with the desired support still missing even when we maxxed out the low-speed compression.

After replacing the spring with the hardest available, the fork proved to be a top performer, responding well to being pushed hard on rough, gnarly terrain.

In its open settings, the fork becomes very firm, which limits the adjustability real-world usage.

We also found the tyre clearence to be quite tight, with Cane Creek giving the Helm a maximum tyre clearance of 2.5in on the 29in model. This made it difficult to attach a variety of mudguards to the fork.

Formula Selva R

Formula Selva R - Enduro suspension fork
Andy Lloyd / Our Media
  • Price: £1,200/AU$2,099 as tested
  • Wheel size/travel options: 120-170mm (29in and 650b)
  • Weight: 2.11kg (29in)
  • Pros: Wide-ranging and user-friendly adjustability
  • Cons: Narrow arch makes fitting mudguards tough with Velcro straps; 160mm brake mount

Formula’s Selva R has impressive adjustability, enabling you to tune it more than most other forks.

The positive and negative air springs are inflated independently, and you can reduce end-stroke progression with the Neopos compressible-foam volume spacer.

You also get Formula’s Compression Tuning System (CST), consisting of swappable valves that change the compression tune, giving you seven different options.

The 2Air system is useful for fine-tuning how the initial part of the travel feels. This gives the fork plenty of small-bump sensitivity, enabling the wheel to hug the ground and making it easy to find grip on slippery trails.

Suppleness over square-edged hits is impressive, too.

We found the Selva R calmed the ride and kept the front end stable, with no harsh spikes deeper in the travel. Over braking bumps, the rebound is fast enough to keep it from packing down and becoming harsh.

Even without the volume spacer, progression was impressive, and we never used full travel, so could run lower pressures to give even more bump-swallowing ability.

Don’t let the narrow 35mm stanchions deter you – whether in high-load berms or big compressions, the Selva R stays composed.

Manitou Mezzer Expert

Manitou Mezzer Expert - Enduro suspension fork
Andy Lloyd / Our Media
  • Price: £700/$815/AU$1234/€864 as tested
  • Wheel size/travel options: 140-180mm (29in and 650b)
  • Weight: 2.09kg (29in)
  • Pros: Impressive performance for the money
  • Cons: Support mediocre; digital pressure gauge is a necessity for setup

The Mezzer Expert comes with Manitou’s ‘Reverse Arch’, which sits behind, rather than in front of, the 37mm stanchions.

External adjustment is limited to a six-position low-speed compression-damping dial, a lockout and a low-speed rebound adjuster.

There’s also a self-equalising negative spring and an ‘Incremental Volume Adjuster’ (IVA), which enables you to change the positive air chamber volume by rearranging self-contained spacers.

The Reverse Arch’s appearance may divide opinion, but it works well enough – the Mezzer Expert’s accuracy through technical sections is good, and we never noticed any binding under high-load turns or sharp direction changes, either.

The fork feels stiff, but not harsh. Blasting along chattery trails, its low breakaway force means it sits comfortably in its sag and soaks up small bumps well, providing tons of grip and confidence in corners and root or rock sections.

Support is mediocre, but it can use its travel and recover from repeated hits quickly. Progression to the end-stroke builds smoothly, with no sharp spike in ramp-up.

We were never hesitant landing drops or ploughing into deep compressions. Pummel through a rock garden and the fork lends a calmness to the front end that helps boost confidence.

Öhlins RXF34 m.2

Öhlins RXF34 m.2 suspension mountain bike fork
The RXF34 m.2 provides good performance at a premium price. - Russell Burton / Our Media
  • Price: £1,185 as tested
  • Wheel size/travel options: 120mm and 130mm (29in)
  • Weight: 1740g (130mm)
  • Pros: Usable range of adjustments; plenty of support without feeling harsh
  • Cons: Pricey

Öhlins' RXF34 m.2 is aimed at downcountry riding with weight saving as a priority.

The RXF34 m.2 uses traditional positive chamber and self-equalising negative chamber in the spring, with volume spacers to increase progression, rather than Öhlins three-chamber design.

We found the chassis to deliver precise steering, with the RXF34 m.2 able to hold a line through tough rocky and rooty terrain better than other lightweight forks.

The mid-stroke has plenty of support, and even with the low-speed compression open the fork remained composed though compressions and high-load corners.

We found no harshness when using the full range of travel, with the fork remaining smooth with zero spiking.

How do I choose a mountain bike fork?

YT Capra Mk III Core 2 enduro mountain bike
Forks can make a substantial difference to how your bike performs uphill and downhill. - Ian Linton / YT Industries

Just like your choice of mountain bike, your choice of a suspension fork should take into consideration the type of rider you are and the severity of the terrain you wish to cover.

There are a multitude of mountain bike forks on the market, from the likes of RockShox and Fox, grouped into sub-categories each intended for a specific use case.

The main differences between the categories are weight and stiffness. Heavier, stiffer forks are favoured by aggressive trail and enduro riders, while lighter forks are popular amongst those riders who value weight savings and don’t require the extra rigidity of a heavier fork, such as XC riders.

Long-travel trail and enduro forks achieve increased stiffness through an all-round beefier chassis, with thicker stanchion diameters (35-38mm) compared to short-travel forks, which commonly have smaller stanchions (32-34mm diameter).

While the chassis often remains similar throughout the price range, the internals housed within vary greatly, with high-end options offering improved performance and tunability over their budget counterparts.

Do all suspension forks fit all bikes?

RockShox Lyrik Select  on the Nukeproof Mega 290 Alloy Pro full suspension mountain bike
Increasing fork travel can void your frame warranty, so have a look at the recommended travel for your frame. - Andy Lloyd / Immediate Media

Based on their intended use, mountain bike frames are designed with a specific suspension fork travel in mind.

Retrofitting a longer or shorter-travel fork can have a big impact on a bike’s geometry, potentially putting excessive stress on the frame. Therefore, it is not uncommon to see brands stating a maximum fork travel for their bikes, a breach of which could impact your warranty.

Increases of 10mm, swapping a 150mm fork for a 160mm option, for example, won’t usually compromise your frame’s geometry too drastically. However, we recommend you check with your frame manufacturer’s guidelines before committing to a fork swap.

How much suspension travel do I need?

RockShox ZEB Ultimate fork - mountain bike suspension fork
Mick Kirkman / Our Media

How much suspension travel you need depends greatly on your riding. If you would describe yourself as a cross-country rider, enjoying big days out on relatively tame paths and trails, you will find the best balance of weight and comfort in a fork with 80 to 120mm of travel with 30 to 34mm wide stanchions.

If you love riding trail centres, with the occasional day out in the mountains thrown in, a suspension fork with 120 to 150mm of travel and 34 to 36mm width stanchions will offer you a good level of comfort and grip at a manageable weight.

If you are an enduro rider and love tackling the steepest and roughest trails around, an aggressive fork with 160 to 180 mm of travel and thick 35 to 38mm width stanchions will offer the best grip, stiffness and comfort at the cost of weight.

If you ride a freeride or downhill bike, you'll want as much travel as possible to deal with high speeds and gnarly terrain. You'll likely already be running a suspension fork with 180 to 200mm of travel with 38mm to 40mm width stanchions.

Air vs coil suspension

MRP's Ramp Control system could give the Ribbon Coil an edge on other coil forks
Coil springs can only be adjusted by switching to a coil with a heavier or lighter spring weight. - Josh Patterson / Immediate Media

The spring in a suspension fork enables the fork to absorb bumps and impacts from the trail. It is usually housed inside the left leg of the fork and can be an air spring or a coil spring.

Coil springs are linear, which means there’s a direct relationship between how much force it takes to compress the spring and how compressed the spring is. For example, a 200lb/in spring will take 200lb of force to compress one inch, 400lb to compress two inches, 600lb to compress three inches, and so on.

They are also linear, meaning that no matter how deep it is in its travel, a coil spring will always compress the same amount under a given load.

An air spring is a sealed cartridge with an internal piston that moves as the fork absorbs an impact, reducing the volume and increasing the pressure in the chamber. Air springs are progressive, meaning that the load required to compress them increases the deeper they sit into their travel.

On modern mountain bikes, air-sprung forks are by far the more popular choice. They are a lot lighter than their coil counterparts and can be easily and accurately adjusted by raising or lowering the internal air pressure with a shock pump to find the perfect setup.

Coil-sprung forks on the other hand can only be adjusted by swapping the coil for another with a heavier or lighter spring weight, which is both costly and time-consuming.

Straight steerer vs tapered steerer

Ohlins RXC34 m.1 carbon steerer tube csu
Jeff Thoren / Ohlins

The steerer is the tube that connects the fork to the bike, fitting through the bike’s head tube before being clamped by the stem and top cap. There are two standards for suspension fork steerers.

The old steerer standard featured a 1 ⅛-inch diameter from top to bottom. These are called straight steerers.

As the name suggests, tapered steerers have a 1.5in diameter at the bottom and taper to a 1 ⅛-inch diameter at the top. Most modern mountain bikes now feature this standard, which is claimed to improve stiffness between the frame and the fork.

A couple of brands have strayed from these standards. Giant ran its Overdrive2 fork steerer system, which tapered from 1.5-1.2in for a number of years, and Cannondale (plus a few other small ebike brands) have run straight 1.5in steerer tubes.

While few bikes deviate from the regular tapered standard, if you have a Giant or a Cannondale, it might be worth checking.

If you have a bike with a tapered head tube, it is possible to fit an older fork with a straight steerer, providing you source an adaptor for the lower headset cup. Unfortunately, the same does not apply to fitting a new tapered fork to an older frame with a straight head tube.

Volume tokens/spacers

Bottomless Tokens
Tokens are usually supplied with new forks. - Jonny Ashelford / Immediate Media

Another benefit of air-sprung suspension forks is their ability to be tuned with volume spacers, sometimes called tokens. These spacers are an inexpensive way to tune the progression of your fork.

By adding volume spacers, you effectively reduce the size of the fork’s internal air chamber, increasing the progressivity of the spring. This enables you to reduce your overall air pressure, increasing the fork’s sensitivity at the start of the stroke without compromising support and ramp-up deeper in the travel.

By removing volume spacers, you can make your fork more linear. This is especially useful for lighter riders who are struggling to use all of their travel and bottom out their fork.

What are compression and rebound damping?

2023 RockShox Lyrik Ultimate and Super Deluxe Coil Ultimate mountain bike suspension fitted to a Marin Alpine Trail XR mountain bike ridden by Alex Evans
Without compression damping, the spring would be uncontrolled. - Mick Kirkman / RockShox

Regardless of whether you have an air or coil spring, the spring itself does a fairly simple job – it absorbs an impact and then returns to its original position.

However, without damping, it is essentially a pogo stick and not very good at delivering a controlled and predictable ride.

This is where rebound and compression damping come into play. Usually housed in the right leg of the fork, the damper is adjusted by dials at the top and bottom of the fork leg.

Rebound damping

2023 RockShox Lyrik Ultimate mountain bike suspension 13
The rebound adjustment is usually found on the bottom of the left fork leg. - Mick Kirkman / SRAM

Rebound damping controls the speed at which the spring returns after absorbing an impact. Too fast and the fork will bounce uncontrollably. Too slow, and it won’t extend in time for the next impact, making for a very harsh ride and compromising grip.

High-speed rebound damping controls how fast your fork will rebound from a big hit that uses most of the suspension travel, while low-speed rebound controls the speed through the rest of the travel.

Luckily, rebound damping can be adjusted on most quality mountain bike forks. Adding rebound damping (often marked ' ' on the fork dial) slows down the return rate of the fork. Reducing rebound damping (often marked '-' on the fork dial) speeds up the return rate of the fork.

Low-speed compression damping

RockShox Zeb Ultimate fork high speed and low speed compression adjustment
Most forks will feature low-speed compression adjustment. - Nick Clark / Our Media

Low-speed compression (LSC) damping influences how the fork responds to impacts where the spring compresses slowly – think pushing into a take-off or around a berm.

Adding low-speed damping makes the fork firmer in these instances, using less travel, and can make for a more supportive and stable-feeling fork at the cost of some sensitivity on small bumps.

High-speed compression damping

The Giant Trance X 1 full suspension mountain bike is equipped with a Fox 36 Performance Elite GRIP2 fork
High-speed compression can stop you from blowing through all your travel on heavy impacts. - Russell Burton / Immediate Media

High-speed compression (HSC) damping is usually only available on high-end forks. It influences how the fork responds to impacts that make the spring compress rapidly, such as sudden compressions and big hits.

Adding high-speed compression damping helps to stop the fork blowing through all of its travel and bottoming out.

How do I know my fork size?

Orbea oiz tyre wheel logo
It's good to check the recommended travel for your frame before purchasing a new fork. - Ross Bell / Orbea

When considering a fork upgrade, it’s important to know the travel and size of your current fork because replacing it with something outside your frame manufacturer's parameters could void your warranty.

Suspension travel is often displayed on the rear of the fork legs, just beneath where the stanchions meet the lowers. If this isn’t the case on your particular fork, you can find the serial number under the fork crown.

The length of the stanchions can also be an indicator of how much travel a fork has. However, it isn’t always reliable because some forks don’t use their full stanchion when compressed.

Another important measurement is the axle-to-crown distance. This is measured in a direct line from the fork crown to the axle.

When measuring this distance, it's important that the fork is unsagged, so make sure the stanchions are fully extended before you grab your tape measure.