Fox Fork Buying Guide

At Westbrook Cycles, we are proud to work with some of the biggest and best mountain bike brands in the world, and Fox is certainly a brand which deserves such accolades. Fox has been around in the world of mountain biking since 2001 - this was when Fox launched their own mountain bike suspension fork, which found instant popularity. The first fork was the 32, and this fork led to the development of the 36 as well as the downhill 40, Fox’s first downhill suspension fork. Fox kept their range large, with plenty of options for all budgets and all riding requirements.

In this post, we look through the current lineup of Fox Forks - studying each range in depth, and also discussing where these forks are best used. The aim of this post is to help you find the right Fox Fork for your bike, your riding requirements as well as your budget. First of all, the naming series of the Fox Fork range is very simple, there is a number in the range - which tells you the diameter of the upper leg - which for those with a little knowledge, tells you what the fork is designed for. The 32 series of forks for example, are designed for cross country use, the 36 range of forks is designed for heavier duty use and the 38 and 40 fork ranges are designed for heavier, downhill use. As well as different sizes, there is also a range of different models with regards to different specifications, which we will cover first:

Factory Series Forks

The Factory Series Forks sit at the very top of the Fox Forks Range. These forks have the very best dampers, which are typically FIT4 and Fit Grip 2 Dampers. Materials used on these forks are also of the highest quality, utilising Fox’s own Kashima coating on the upper legs of the fork, which has been proven to reduce friction on the fork, increasing performance, reliability and longevity of the fork. The Kashima coating also increases fork performance, by creating microscopic pores on the upper legs that lubricate the fork with oil as the fork compresses and rebounds - allowing the rider to enjoy smoother operation.

Performance Elite Forks

The Performance Elite range of forks sits in the middle of the Fox Fork range. They use the same high end damping and dampers used on the Factory Series, but do not have Kashima coating - instead, the upper legs of the fork have an anodised black finish.

Performance Forks

Performance Forks are the entry level fork range of Forks from Fox. These forks still provide great performance, but use a simpler damping system and again the upper legs of the forks are black anodised. The bottom of the forks however, share the same parts as the more expensive forks within the range.

Rhythm Forks

You will only see Rhythm forks on fully built bikes, and rhythm forks are an OEM choice for many bike manufacturers. These forks have a GRIP damper and are constructed from aluminium.

Step Cast Models

The Step Cast range of bike forks are only available in the 32 and 34 series, and for good reason. These forks are designed for lightweight cross country performance, and these forks have a narrower design, and also stepped lower legs - all with the aim of reducing weight and are ideal for riders looking for lightweight suspension forks.

Fox E Bike Forks

Fox have adapted and developed their own range of e-bike forks, these forks are available in the 34 and 36 models - and are essentially beefed up versions of normal forks, which are designed to cope with the extra bulk and weight of an electric mountain bike.

Fox 32 Forks

Looking now at the numbered range of forks, the Fox 32 range of forks is available in Step Cast, Factory and Performance specification. Regardless of the specification, these forks have 100mm of air sprung travel. As standard, these forks have a tapered steer as well as a 15mm thru axle.

Factory level forks have the acclaimed FIT4 damper, which has three different positions for adjustment as well as rebound adjustment. There is also a bar mounted lockout available within this specification. The Fox 32 Performance Fork has a three position GRIP damper, with different travel options available from 100mm, 120mm and 140mm suspension travel.

There is also a special edition fork which is the 32 Step Cast fork, which is known as the Fox Step Cast AX as well as the Adventure Cross. This fork has just 40mm of travel and is designed for use on gravel bikes.

Fox 34 Forks

Kicking off the range of 34 forks, is the 34 Step Cast range of models - these forks are lightweight in their design, and are only available in 29 inch wheel size. There are 100mm and 120mm travel options. These forks have Kashima coated legs as well as the FIT4 damper. 

There is also the 34 step cast performance fork, which again is only available in 29 inch wheel size - as well as a 120mm of travel, with a GRIP three position damper.

At the top of the 34 range is the 34 Factory. This fork is packed with innovative tech and has a Fit4 three position damper, it’s only available in a 29inch wheel option but there are 130 and140mm travel options. This fork has a 15mm axle and can fit a tyre size up to 2.6 inch. As  expected, this fork has Kashima coating for optimal performance and reliability.

Going down one model in the range is the 34 Performance Elite fork. This fork has a three position damper, and is only available in 29 inch wheel size. This fork has 130mm of travel and fits up to a 2.6 inch tyre and uses the FIT4 damper. The base model within the range uses a three position damper, and has 140mm of travel.

Fox 36 Forks

The Fox 36 range benefited from a major overhaul in 2021, and these forks became more of a long travel bike fork. There were also a host of new features launched, such as air bleeders on the lower legs of the fork, new and improved internal channels which removed pressure from the lower part of the forks, as well as floating axles and the latest EVOL air springs and the FIT GRIP2 Damper.

As expected, at the top of the range is the Fox 36 Factory Fork which is available in 29, 26 and 650b wheel sizes. This fork only comes with an EVOL Float Air spring. The 650lb fork has 150 and 160mm travel options, and the 329 inch fork comes with 150mm of travel options using a FIT4 and the FIT GRIP2 models are available with both 150mm and 160mm of travel.

The Fox 36 performance Elite forks use a FIT GRIP 2 Damper and have 160mm of travel, they also have boost spacing as well as a tapered steerer. The 36 E-bike Factory Fork is a 29inch fork which has 160mm of travel, using either a FIT Grip2 or FIT4 Damper - these forks also have boost spacing as well as a tapered steerer, with plenty of travel options from 140mm to 180mm.

There is also a 36 E-bike performance fork in a Boost 29 inch option, which has 160mm of travel, black anodised legs and a three position damper.

Fox 38 Forks

The Fox 38 fork has been designed to be a hard hitting long travel suspension fork, ideal for enduro bikes. This fork has bleeders on the suspension legs, it also has new internal channels as seen on the 36 range to reduce the build up of pressure in the lower parts of the suspension fork. The 38 range uses the EVOL air spring, and also has a Fit GRIP2 Damper, the 38 also has a steerer tube to support areas of high stress on the fork.

At the top of the range sits the Fox 38 Factory, which has a FIT GRIP2 damper with 160mm-180mm of suspension travel. As you would expect, this fork is coated with Kashima - so runs incredibly smoothly. Further down the range is the Fox 38 Performance Elite, which has 170mm of travel and a FIT GRIP2 Damper. The Fox 38 Performance Fork has 170mm travel with a GRIP damper, and there’s also a Kashima Coated Ebike 38 fork, which has 180mm of suspension travel.

Fox 40 Forks

The Fox 40 Fork which is available on the market are all Kashima coated, and are Air Sprung. There are a number of different wheel size options available, 26 inch, 650b and 29 inch wheels are all catered for. All 40 forks have 203mm of suspension travel. These forks, like many within the Fox range underwent a revision in 2021, with air channels added and chassis changes made. The Fox 40 performance level forks are only spec’d on new bikes as OEM parts.

Why Choose and Use Fox MTB Forks?

Float EVOL Air Spring

The air spring system is used across the entire fox fork range. The Evol in the name stands for Extra Volume. This air spring has a larger negative air spring compared to previous models, meaning that the travel from this spring is more linear.

FIT 4 Damper

The Fit 4 Damper is one of Fox’s premium dampers. This damper has a three position compression adjustment which is done via a blue lever, with a black lever also providing fine tuning adjustment in open mode via a black knob. There is also a two position lockout available. There’s rebound adjustment at the bottom of the fork, and there’s also a rubber bladder for displaced oil as the damper cycle goes through the travel.

FIT GRIP Damper

The Fit Grip Damper is the damper which is fitted to most mid-range Fox Forks. This damper provides good levels of performance, and has a three position compression damper adjustment. This adjustment is carried out by an easy to use blue lever at the top of the fork. The damper also uses a semi sealed cartridge that allows a sprung piston to compensate for oil, which allows the user to bleed excess oil as needed.

FIT GRIP2 Damper

The Fit Grip 2 Damper is found on the downhill forks within the Fox range. It works in the same way as the FIT GRIP damper, sharing many technologies - using a sprung piston. The difference comes in the level of adjustment available on the Grip2. As well as high and low speed compression damping, there is also high and low speed rebound damping which can be adjusted too.

Variable valve control adjusts the high speed rebound damping - which works by altering valve flex rather than preload - allowing greater control, without the need to take the damper apart.

The FIT Grip2 damper also has a different mid valve compared to other dampers in the range, as well as friction reducing treatments, providing smoother operation over other Fox Dampers.

Kabolt Axle

Kabolt Axles replace the 15mm flip lever axle found on fox forks. This Kabolt axle main purpose is to save weight on lightweight forks.

Kashima

Kashima Coatings are found on the top of the range Fox fork models/ This coating has lubricating molybdenum disulfide which is deposited into the fork through billions of micropores of the aluminium fork. Scientific talk aside, this coating means that the forks remain better lubricated, which equals not only better performance, but also a better lifespan.

Lower Leg Channel

The latest versions of the 36,38 and 40 forks have lower legs and air channels that have been designed to increase the amount of air volume in the lower leg of the fork. When the fork compresses, the air in the fork acts like another spring - meaning that it’s harder to bottom out the fork completely. This volume of air means there is less ramp up effect, and also provides a better path for the oil in the fork to reach higher up - meaning a smoother operation.

Volume Spacer

All Fox Shox Forks allow the rider to control how progressive the stroke of the fork is. This is done by adding or removing volume spacers. This is done by undoing the top cap of the air spring side leg, and adding or removing clip on spacers. Adding spacers means that there is increased resistance to when the fork bottoms out, and removing them lowers the resistance to bottoming out.