A decent fork is essential for getting the most out of mountain biking.
When mountain bike suspension forks began appearing they revolutionised riding. Suddenly you could ride faster and tackle rougher terrain in more control and greater comfort. And even after all that time, their significance hasn’t diminished one iota.
As the first wall of defence against roots, rocks and bumps, they help isolate you from a constant battering, and keep your front rolling forward and your tyre tracking the ground, ensuring you can still brake and steer, even when grip is compromised.
With this in mind, plugging the best suspension fork possible into the head tube of your bike is absolutely paramount.
First of all though you need to make sure the fork will fit – and suit – your bike.
Work out your standards
Not all forks will fit – or suit – all bikes. There are varied wheel sizes, axle types, fork steerers and amounts of suspension travel that need to be observed and adhered to.
Here are the five standards that you need to get right…
1. Wheel size
There are three wheel sizes kicking around the mountain bike world: 26in, 27.5in (also known as 650B) and 29in. You cannot mix and match forks and wheels. The fork must be designed for your bike’s wheel size.
If you’re not sure what wheel size your bike is, look at the tyres. The wheel size will be written on the side somewhere.
2. Fork steerer
These days pretty much all mountain bikes accept the tapered steerer standard. Some older bikes will only accept 1 1/8th steerers.
3. Axle types
The majority of modern mountain bikes will have 15mm bolt-thru axles. Older and/or cheaper bikes may have 9mm quick release. Some older and/or longer travel bikes may have 20mm bolt-thru axles.
4. Disc mounts
Modern mountain bikes and forks will have Post Mount disc brake callipers. Older bikes and forks may have I.S. mount.
5. Amount of travel
Bike frames are designed around a fairly specific amount of suspension fork travel. Don’t be tempted to run a long travel fork in a frame designed around a short travel fork. You’ll seriously foul up the bike’s handling.
You don’t have to stay rigidly within the same mm of travel. You can usually get away with running a fork with up to 20mm longer travel in a bike before the handling goes screwy.
Don’t ever run a fork with shorter travel than the frame is designed for, the steering will be dangerously twitchy and your lowered bottom bracket height will result in incessant pedal strikes.
Choose your spec
Once you have worked out (and written down!) all the standards that you need your new fork to have – eg. 27.5″ wheel, tapered steerer, 15mm axle, Post Mount disc, 140mm travel – it’s then time to decide what features you want/need on your new fork.
More features cost more money. More features can be confusing. More features to go wrong. More features can weigh more. But a lot of riders do get more out of their suspension by having more features.
Be honest with yourself about what sort of rider/person you are. Even pared-down forks with minimal features are really good these days. And if you don’t know how to adjust extra features properly you can end up with badly setup fork that works worse than a basic fork.
Watch: Six common suspension mistakes
If you don’t yet know much about how to set up or adjust suspension then read or bookmark our How to set up mountain bike suspension guide. It’s full of useful information and advice that will help you get the most out of your fork.
All forks will have adjustable rebound damping. Rebound damping controls the return speed. It’s usually adjusted at the bottom of the fork via a dial.
Fatter legs are stiffer. Fatter legs are heavier. If you’re a heavier rider, a more aggressive rider, a 29er rider – fatter legs are worth having. Look for forks with at least 34mm diameter stanchions.
Bolt thru axle designs
They’re all much of muchness in terms of stiffness and weight but some are easier to operate than others. Some require tools, some can just be done with your hands.
If you’re forever taking your front out (to fit in the car boot for example) then a faffy tools-required axle design will be very annoying.
Air or coil sprung
Coil springs are an increasingly uncommon sight on mid to high-end suspension forks. Only cheap entry level forks and forks designed for Downhill and Freeride applications have coil springs nowadays.
Air is the perfect spring medium for lightweight suspension forks because it doesn’t weigh anything and it can be set up for riders of any weight. Forks use a single Schrader valve to adjust the main air spring.
Some – but not all – fork even come with a shock pump included in the box for this purpose. Check this before you buy because you WILL need one and they cost about £20 otherwise.
Low-speed compression adjusters control weight shifts, reduce bobbing and help prop the fork up on steep descents. High-speed damping is designed to control higher shaft speeds, for example when hammering through a rock garden, or a rooty section of trail.
Normally, compression dials live at the top of the fork, and some even give independent control of both high and low-speed damping.
Watch: How to put volume spacers in your fork
Adding volume spacers to the fork reduces the size of the spring chamber, causing it to ramp more as it moves through its travel. You can then reduce the air pressure slightly to improve sensitivity without it bottoming too easily.
The weight of forks can vary surprisingly. It’s always worth glancing at the weight of a fork that you’re considering. Cheaper forks will use heavier, less sophisticated materials in their construction.
Weight is not a very glamorous ‘feature’ as such but it shouldn’t be neglected. A heavy fork with loads of adjustments is still a heavy fork that weighs you down. Less can be more with suspension.
SunTour Auron 130mm fork
There’s a wide range of adjustment on all three dials, but the Auron is overdamped on both low-speed and high-speed compression, especially for mid-weight riders. Hence, it feels pretty dead, with very little sensitivity over small bumps.
DT Swiss OPM ODL 130mm fork
With its low weight, firm damping and 130mm travel, the DT Swiss ODL may suit a short-travel trail bike, but it needs updating for anything with longer travel.
RockShox Pike RCT3 140mm
On the trail, the Pike is totally unfazed. It has excellent small-bump sensitivity, but it remains unruffled on big hits and through rock gardens. The fork soaks up stutter bumps without breaking its stride.
Fox Float 34 Factory Series 140mm
Following in the footsteps of the new 36, the 34 is also confidence-inspiring and lets you push harder and faster without feeling on the ragged edge.
X-Fusion Trace Roughcut 140mm
Previous X-Fusion forks we’ve tested didn’t always work as well as those from bigger brands, but were usually better value. The X-Fusion Trace now offers comparable performance, but has nearly doubled in price, and it still needs a bit of tuning to the spring progression.
Marzocchi 350CR 160mm
With its super-stiff chassis, the 350CR is well-suited to heavy riders looking for a solid, reliable, 160mm fork. Marzocchi has a well-earned reputation for super-plush forks, and the 350CR is no exception, the sensitivity improving dramatically as it beds in.
Manitou Mattoc Pro 160mm
The supple, coil-like feel, kept the fork planted. Even smashing through the rocks at BikePark Wales, the Mattoc Pro was totally unfazed, and we never had any issues with excessive diving or harshness in the damping.
RockShox Yari RC 160mm
This is an excellent 160mm fork for the money — stiff, reasonably light and you couldn’t set it up badly if you tried.
SunTour Durolux R2C2 160mm
The level of adjustment on this fork is amazing; unfortunately, there are a couple of niggles. It’s noisy and the Q-Loc axle is truly annoying.
X-Fusion Sweep 160mm
The Sweep just doesn’t have the grip levels of the Manitou Mattoc or RockShox Yari. X-Fusion is playing catch-up, because there are better options on the market right now.
Bos Deville 3-Way TRC 160mm
The silky smooth action of the Bos Deville means that traction and comfort on loose, rough trails are both first rate. Push it flat-out through root and rock and it’s cool as a cucumber.
DVO Diamond 160mm
As it stands, the Diamond is ultra-plush and can withstand a lot of abuse. If DVO really wants it to stand out in this ultra-competitive category, however, the Diamond needs a little polishing.
Fox 36 Factory Series 160mm
Surprisingly, with a firm set-up, the 36 still offered unparalleled control in rough terrain, where the extra support on steep tracks has got to be worth a couple of degrees in the head angle alone.
RockShox Lyrik RCT3 Solo Air 160mm
It’s easy to get a good baseline setting on the Lyrik. Add air and low-speed compression and you’re good to go. Solid, reliable and easy to set up, the new RockShox Lyrik offers first class performance at a knock-down price.
In the 130mm to 140mm travel range, even though the Fox Float 34 came second-best in this test, it’s still an amazing trail fork. It’s lighter and cheaper this year and is available in all three wheel sizes and with a ton of travel options. If we could have rated it a 9.5, we would.
We’ve tested the RockShox Pike RCT3 against both the new Fox 36 and the older Fox 34 CTD, and it has come out on top both times. It’s obvious from this that the Pike covers a wide spectrum of riding, and is incredibly versatile, but it is carrying a bit more weight.
In the longer travel 160mm forks, the more affordable Manitou Mattoc Pro just shaded it. Admittedly it’s not the stiffest fork on test, but it’s lightweight and we could easily dial it in for any terrain or rider weight. Our test fork has also been totally reliable and hasn’t put a foot wrong.
The higher end 160mm fork winner was the superb RockShox Lyrik RCT3 Solo Air. It’s ridiculously easy to set up and an absolute bargain.