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For more than 47 years, FOX has been designing and manufacturing world class suspension that’s purpose-built with the specific goal of going hard and fast – and being built to last.

We got our start by revolutionizing motocross suspension in the ‘70s and since then we’ve gone on to developing category-leading suspension for everything from mountain bikes to trophy trucks and most everything in between. Our well of suspension knowledge for all things off-road runs deep.

We approach e-MTB suspension with the same podium-proven dedication and attention to detail

While FOX e-MTB forks might look virtually identical to our standard MTB forks from the outside, there’s a lot more going on inside than meets the eye. This is because we approach e-MTB suspension with the same podium-proven dedication and attention to detail as we do with every single category that we make suspension products for – we look at the specific needs and demands of the application and then we design for exactly that, down to the smallest degree. No two riders’ needs are exactly the same and there are many different types of e-MTBs on the market.

Because of this, FOX has three distinct e-MTB specific suspension offerings to suit all riders: e-MTB Tuned, e-MTB Optimized, and e-Live Valve, each with distinct feature sets as described below.

38 E-Tuned

e-MTB Tuned
FOX’s e-MTB Tuned forks feature the same chassis as our standard forks except with a custom damper and air spring tune for the slightly different ways in which e-MTBs are ridden as compared to standard MTBs. For example, e-MTBs allow riders to conquer technical rolling terrain with greater ease than is possible on a standard MTB. In order to utilize the assistance provided by the bike in this type of riding the rider must keep pedaling. It’s difficult to maintain traction while pedaling over rough terrain. Therefore, our e-MTB Tuned forks feature a custom compression tune that helps keep the wheels glued to the ground at all times, maintaining traction and forward momentum, and a more progressive air spring tune to make sure that even though the initial stroke is softer the end stroke ramps up to provide the right amount of support for those bigger hits. These may seem like subtle differences but optimizing to even the smallest degree is a trait we’ve learned the importance of over our many years of winning races – sometimes by the smallest of margins.

36 E-Optimized

e-MTB Optimized
FOX’s e-MTB Optimized forks not only receive the same special damper and air spring tune as our e-MTB Tuned forks, but they also receive beefed up aluminum alloy CSUs (Crown, Steerer, and Upper tubes) assemblies in order to meet our internal stiffness and strength requirements, as well meeting or exceeding EN, ISO, and ASTM testing requirements for e-MTB use cases on Class 1, and Class 3 e-bikes with increased system weight ratings. The one exception to this labeling is our hard-hitting 38, which is already burly enough to meet these requirements without needing any chassis reinforcements. Therefore, when you see an e-MTB Tuned 38 you can rest assured it’s ready for whatever you can throw at it.

38 Live Valve

e-Live Valve
e-Live Valve signifies an e-MTB damper tune paired with FOX’s proprietary Live Valve electronically controlled suspension system, which faster than the blink of an eye automatically adjusts the bike’s suspension based on the terrain. e-Live Valve runs directly off the same battery that provides the pedal assist and therefore requires no additional battery pack or separate charging. E-Live Valve uses and advanced communication protocol that draws incredibly low power and does not notably affect range. E-Live Valve is an integrated system and therefore is only available on select complete e-MTB bicycles.

34 E-Optimized
34 E-Optimized
34 E-Optimized
34 E-Optimized
34 E-Optimized
34 E-Optimized
36 E-Optimized
36 E-Optimized
36 E-Optimized
36 E-Optimized
36 E-Optimized
36 E-Optimized
38 E-Tuned
38 E-Tuned
38 E-Tuned
38 E-Tuned
38 E-Tuned
38 E-Tuned



What is the difference between e-tuned and e-optimized?
E-tuned focuses on the tuning of the fork’s damper, while e-optimization focuses on alterations to the fork’s chassis.

Why isn’t there an E-optimized 38?
The 38 exceeds our stiffness benchmark for eMTB applications, therefore it only requires an eMTB-specific tune.

Can I purchase an E-Live Valve system in aftermarket?
No. We do not offer E-Live Valve system in aftermarket, only on OEM complete bikes.

Do e-optimized 36’s use the same air spring as standard 36’s?
No, the piston diameter is smaller to account for thicker stanchion walls.

Can I run a standard 36 or 38 fork on my e-bike?
You can run a standard 36 fork on a Class 1 eMTB with a max system weight of 140Kg. You can run a 38 fork on a Class 1 or Class 3 eMTB with a max system weight of 169Kg.

Do you sell eMTB-specific rear shocks?
No. Rear shocks on ebikes are tuned to the bikes, if you want to explore custom tuning options, please explore tuning options with our FOX Factory tuning program.

Are Transfer seatposts eMTB rated?
Transfer’s are compatible with Class 1 and Class 3 eMTBs with a system weight up to 169Kg.

Is the FOX 40 ebike rated?
It’s compatible with Class 1 eMTB’s with a max system weight of 140Kg

Are Kabolt X axle’s compatible with EMTB forks (are they strong enough and rated for eMTB)?
Yes. The Kabolt X axle has been tested up Class 3 and 169Kg system weight limit.

Why don’t you make different lowers for e-optimized 36’s?
When lower legs are properly engineered and designed, they pass all standard MTB and E-bike+ lab and field test requirements. In the interest of common parts and quick service, it is advantageous to the customer to have a common lower leg for both standard MTB and E-bike+ fork applications.

What is the weight difference between a E-optimized 36 and a standard 36?
E-optimized 36 is 227.5g [0.50 lbf] heavier than the standard 36.