With fork technology evolving, the singletrack is getting faster and faster - our pick of the best mountain bike forks will help you run smoother.
If you’re looking to make a significant improvement to a mountain bike’s ride quality, upgrading to the best mountain bike suspension forks is a smart option. The top models are likely to be one of the biggest investments you’ll make, but they pack the potential to totally transform your riding experience. air suspension for cycle
Fox Float 38 Performance Elite offers all the adjustments of the Factory model, at a slightly cheaper price.
Weight: 2,360g | Travel: 160-180mm | Wheel sizes: 27.5 or 29in | Rating: 10/10
Fox’s flagship single-crown fork is also our ultimate upgrade choice. As long as you have the budget, this burly-legged bruiser takes the roughest tracks in its stride. It’s more sensitive and slightly more composed than the RockShox Zeb, even if the adjustments are not quite as user-friendly. Indeed, in back-to-back testing at BikePark Wales, the 38 clearly had the edge over the RockShox Zeb on the same tracks on the same day, to the point we started to think that our Zeb was in need of a service.
As long as you’re careful and methodical with the dials, you can dial-in this fork exactly how you want it, and then its just a case of hammering as hard as you can, because the Fox 38 just keeps on coming back for more.
Read our full test review of the Fox Float 38 Performance Elite
Fox 36 Factory GRIP2 is perfect for most riders and even works well on e-bikes up to 160mm travel.
Weight: 2,220g | Offset: 44mm or 51mm (29in), 37 or 44mm (27.5in) | Travel: 150 or 160mm | Rating: 10/10
While it’s tempting to assume you need the extra strength and stiffness of the stout 38, many riders will actually be better off on the erstwhile 36. Why? Well it’s lighter and the chassis is still plenty stiff enough at popular trail bike travel. And the slimmer legs can actually help reduce harshness on mega-stiff carbon e-bike frames.
It still gets the same soft initial touch and reliable support as the 38, and the adjustments are just as wide and effective. We love the new chassis with its lower leg lubrication channels, that splash oil over the bushings and seals to keep it smooth and sensitive. And the pressure bleeders are a useful addition on hot days and long descents. Even the new dropouts can really help reduce binding and keep the ensure you’re maximising performance. As we said in our review, “the latest Factory 36 feels like floating in a bath of oil, but also informs enough about the terrain to ride precisely and actively by never being too wallowey or mushy”. So there you have it.
Read our test of Fox 36 Factory GRIP2 fork
For half the price of the most expensive forks, Marzocchi’s Bomber Z2 Rail delivers excellent performance.
Weight: 2,010g | Offset: 44mm, 51mm | Travel: 100, 120, 130, 140, 150mm | Wheel sizes: 27.5 or 29in | Rating: 9/10
Essentially a Fox 34 Rhythm in drag, the Marzocchi Bomber Z2 Rail offers excellent performance and low-maintenance at an affordable price. Everything is built big and burly to last, so it’s not the lightest fork on the block, but it needs less time in the workshop and less fettling by the trail-side to set-up.
Given the price, the Z2 is a surprisingly capable fork and responds well to being ridden hard. The highlights are the grip as there’s very little harshness, and it feels solid and secure landing big jumps and drops. As such it fits Marzocchi’s image as a freeride brand. To lift a quote from our review, “if you just want minimal faff and maximum ride time, the Z2 is ideal”.
Read our full test test review of Marzocchi Bomber Z2 Rail fork
RockShox SID Ultimate blurs the lines between XC and trail riding.
Weight: 1,508g | Offset: 44mm | Wheel size: 29in | Travel: 120mm | Rating: 10/10
In many ways, we think the SID is the best fork in RockShox’s current range. It’s impressively light, bringing noticeable and significant weight savings, yet it’s sensitive, supportive, and stout enough for rallying hard. To spearhead a top down-country chassis, such as the Transition Spur, it’s a match made in heaven.
We’re mainly talking about the 35mm version, with 120mm travel, leaving the skinnier 32mm option for racing only. There’s a bit of flex under extreme loads, but given the SID’s weight and remit, it’s perfectly acceptable. Overall, the SID is an incredibly impressive fork that arguably bridges the gap between the masochistic world of XC racing and the baggy shorted smile-time of trail riding.
Read our full test review of the RockShox SID Ultimate
For simple set-up and a stout chassis, the RockShox Zeb Ultimate is a great choice.
Weight: 2,280g | Wheel sizes: 27.5 or 29in | Travel: 150-190mm | Offsets: 38mm, 44mm (27.5in), 44mm, 51mm (29in) | Rating: 9/10
Although the Zeb is slightly less adjustable than its rival Fox 38, it is a bit lighter, and more importantly is cheaper. There’s no lack of stiffness, so it’s a great upgrade for a long-travel e-bike if you’re a heavier rider.
The damper is easily adjustable, with dials that can be tuned like an amplifier, rather than endlessly rotated as you try to remember the clicks. And the adjustments really make a noticeable difference, too. Which encourages you to make changes on-the-fly and really dial in your set-up. Having ridden loads of Zebs and just as many Fox 38s, our experience is that the RockShox product has more damping and a more stuck-to-the ground feel, compared to the 38’s supple yet supportive response.
Read our full test review of the RockShox Zeb Ultimate
The icing on the cake of any short travel trail bike: The Fox 34 Float Factory.
Weight: 1,770g | Offset: 44mm, 51mm | Travel: 130mm, 140mm | Wheel sizes: 27.5 or 29in | Rating: 10/10
34 diameter upper tubes may seem weedy in a world of 38mm options, but for most trail bikes with 130-140mm travel, they have ample stiffness. And the pinnacle of the trail bike fork market is the Fox 34 Factory, thanks to its impeccable damping and perfectly tuned air spring.
The performance of the 34 is exceptionally fluid and controlled, so it provides ample comfort and never gets flustered. The new chassis helps circulate the oil for improved consistency, and the four-way damping adjustments mean you can always get the right tune. Not a cheap prospect, but the ultimate performance usually comes at a cost.
Read our full test review of the Fox 34 Float Factory GRIP2
Smooth as silk: The Cane Creek Helm Coil MKII
Weight: 2,400g | Offset: 44mm | Travel: 130-160 (internally adjustable) | Rating: 9/10
Coil-sprung forks are a rarity these days, but Cane Creek puts up a convincing argument that they still deserve a place at the top table. The Helm Air MKII comes in both air and coil options, and we’ve tested both, and rated them highly, but its the coil version that really got us excited. It also stands out as one of the few coil options on the market. So why the hype? Well, in our review we were blown away by the quality of damping and reduction in harshness. In turn, that meant more control and less fatigue, so we could take stupid lines, and push harder for longer. It was almost like cheating.
Yes, the coil spring adds weight and doesn’t have the breadth of convenient adjustability of an air spring, but if you’re looking for something left-field, and are already sold on the advantages of coil-sprung shocks, the Cane Creek Helm Coil could be the perfect complement.
Read our test of Cane Creek Helm Coil MKII
Which is the best fork? The suspense is killing me…
With plenty of time to put these forks through their paces, we ended riding everywhere from uplift days at BikePark Wales, Dyfi Bike Park and Revolution Bike Park, to big days out hammering Lake District bedrock. The forks here also either did extended time on Alpine riding trips, being pummelled by 10,000s of metres descending, or faced accelerated forces bolted to various all- mountain e-bikes.
All forks were then back-to-back tested systematically on the same bike (in the dry for maximum speeds and loads) on a local test track. The track we chose had a good mix of steep, twisty ruts up top and then high-speed, beaten-up braking bumps and berms towards the bottom. It’s a track known intimately to all test riders and chosen for how hard it works even a modern suspension fork.
RockShox’s latest and greatest Zeb Ultimate fork
With suspension brands continually updating their products for improved performance, fork technology is a constantly evolving landscape. Leading players like Fox and RockShox will be familiar as original equipment on complete bike packages, while he smaller firms here have big ambitions for a slice of the aftermarket pie. With trickle-down development from oher areas such as motocross and rallying, there’s a really broad approach to design, technology and tunability among the brands represented.
Considering a fork literally just has to slide up and down to absorb bumps and stabilise the rider, a huge amount of R&D and technology lurks inside. Chassis stiffness, weight, damper architecture, seal and bushing friction, and adjustability are just some of the factors suspension engineers strive to improve. Forks also have to work for a wide range of rider styles and weights.
Most high-end forks come with mind-boggling adjustability, but whether you’re a suspension expert, or you just want to enjoy more speed, comfort and control, for this buyer’s guide put in the hard miles to really get to the bottom of which model delivers ultimate performance on the trail.
Air-sprung forks support rider weight with a tuneable air cushion. Air pressure is added via a Schrader valve with a specific high-pressure shock pump to tune ride feel and adjust spring rate and support.
These aren’t used on every fork, but tweaking the size of the (positive) air chamber by adding or removing volume spacers (or in-built systems to do the same) affects the spring curve. More spacers increases spring progression and helps prevent harsh bottom-outs, while fewer spacers (a larger internal volume) softens the end stroke. Öhlins uses a separate, third, ramp-up chamber to tune progressivity.
Dials on the top and bottom of the fork legs adjust parameters to tune support and control. Separate damping dials allow specific tuning options as to how much oil is allowed through ports and shims inside to absorb impacts, but more options also introduce more opportunities to mess up settings. Having said that, most suspension brands and bike companies now offer decent tuning guides according to body weight, and these will give you a good start point to work from.
Stanchion diameter is an important metric for overall stiffness, with thicker fork legs generally adding weight. Bushing size and overlap, plus crown and brace construction also affect rigidity. Tapered steerer tubes are the norm – 1 1/8in to 1.5in at the base. Lower-leg assemblies use cast magnesium to save weight, and all forks here use a Boost 110mm axle spacing with quick- release-style or Allen-key fixings.
Within the air spring there are typically two separate elements balancing breakaway friction and small-bump sensitivity against support. A negative spring pushes back against the main positive spring, and either takes the form of a separate (automatically equalising) air chamber or a coil spring.
Fork rake or offset has evolved as an important design element. Most brands now offer two different offsets in each wheel size, ranging from 37mm up to 51mm. It’s complicated, but offset affects steering feel and tyre stabilising force, so shorter offsets offer more stability and a ride quality that emulates a slacker head angle, while still keeping the bike’s wheelbase shorter.
Compression damping controls the rate at which displaced damper fluid is allowed to move during bump events. Low-speed controls low shaft-speed impacts like body weight shifts and rolling terrain, and high- speed damping absorbs harsh impacts like square bump faces and landings. Forcing oil through ports or shim stacks generates damping resistance, with energy converted into heat.
High Speed Rebound, Low Speed Rebound
air shock pump This is the damping circuit that controls the speed that the fork returns to sag after a bump event. Low-speed damping is the most common external adjustment. The damping circuit uses orifices and shim stacks to regulate the oil flow – ports can be opened or closed and shims made stiffer or softer. Some systems also act ‘dynamically’ and respond differently according to the shaft speeds (the speed the legs slide up or down).