EXT Ferro USD 36 E-MX Upside-Down Suspension Fork

Finally, a performance upside-down suspension fork engineered exclusively for high-output electric dirt bikes and heavy e-motos. EXT Racing Shox introduces the EXT Ferro USD 36, an inverted 36mm stanchion front fork designed to complete your ultimate E-MX build. Built around hard heat-treated chrome-moly steel stanchions with a Superfinish surface treatment, 7000-series aluminum upper legs, and a dedicated drop-crown triple clamp system, the Ferro USD 36 delivers maximum torsional rigidity and minimal flex under extreme trail braking and cornering.

Available straight through Electri Cycle Works with optional pre-installation prep services, the EXT Ferro USD 36 boasts 205mm of travel and fits both 19-inch and 21-inch front wheel setups. Driven by EXT’s acclaimed HS3 hybrid air spring technology and a high-flow 3-way adjustable hydraulic cartridge, this fork brings world-class tuning, bottom-out control, and plush sensitivity to heavy-duty off-road electric motorcycles.

EXT Ferro USD 36 Fork Key Performance Highlights

• 36mm Heat-Treated Chrome-Moly Stanchions: Constructed from 42CrMo4 steel with Superfinish surface treatments for low friction and torsional stiffness.

• HS3 Hybrid Twin-Air Spring System: Features two separate positive air chambers paired with a large, self-equalizing negative air chamber to deliver mid-stroke support around your dynamic sag position while maintaining small-bump sensitivity and bottom-out protection.

• 3-Way High-Flow Damping Cartridge: Independent High-Speed Compression, Low-Speed Compression, and Rebound adjustments let riders dial in precise hydraulic control for aggressive riding and varying terrain.

• CGB Continuously Guided Bushing System: Mobile sliding DU bushings featuring super-long static overlap ensure maximum guidance, low hysteresis, and reduced side-load binding under heavy impact.

• External Pressure Release Valves: One-way pressure release buttons on both legs make bleeding built-up leg air quick and simple between trail rides.

• Floating Axle & 200mm Brake Mount: Equipped with a 20mm boost-compatible twin-hexagonal floating axle and a direct 200mm post-mount disc brake setup.

Optional Pre-Installation Service Package

Make installation seamless by selecting our pre-installation service at checkout. Our Electri Cycle Works suspension technicians handle all the complex preparation steps before your fork ships out:

• Steerer tube trimmed directly to direct-mount length.

• Star nut installed (or prepped for your stem lock system upon request).

• Lower headset bearing pressed, greased, and seated correctly.

• What you’ll still need for home install: Steerer tube spacer set and a Boost spacer kit. (Note: If installing on an MX4 or E Ride Pro SS, a 220mm brake rotor adapter is required).

 Detailed Specifications Matrix

Feature Category	EXT Ferro USD 36 Technical Specifications
Retail Price	Official Factory Pricing (Check price at checkout)
Fork Architecture	Inverted (USD) E-MX Dual Crown
Stanchion Specs	36mm Hard Chromed 42CrMo4 Steel with Superfinish
Upper Legs & Crown	7000-Series Aluminum Dedicated Drop Crown
Front Travel	205 mm
Fork Offset	44 mm
Wheel Compatibility	Fits 19″ and 21″ Front Wheels
Air Spring System	HS3 Tech (Twin Positive + 1 Large Negative Chamber)
Damping Adjustment	3-Way Adjustable: Independent High/Low Compression + Rebound
Axle Standard	∅20mm Twin Hexagonal Floating Axle (Boost Compatible)
Brake Mount Standard	200mm Post Mount (220mm adapter needed for MX4 / E Ride Pro)
Total Weight	4,500 grams (9.9 lbs)

Why Buy From Electri Cycle Works?

• Authorized E-Moto Suspension Specialists: Expert support, installation advice, and custom valve tuning setup guides from riders who know e-moto platforms inside and out.

• Ready-To-Ride Options: Save time and shop visits with our pre-cut steerer tube and pressed bearing install kit options.

• Fast Delivery & Local Pickup: Order online for quick nationwide shipping or direct pickup at our Salt Lake City showroom.

Frequently Asked Questions

What front wheels work with the EXT Ferro USD 36?

The EXT Ferro USD 36 drop-crown setup is engineered to clear both 19-inch and 21-inch front off-road wheel assemblies.

Do I need additional parts to mount this fork on an E Ride Pro SS or Talaria MX4?

Yes. When running a 220mm brake rotor on an E Ride Pro SS or Sur-Ron / Talaria MX4 platform, you will need a 220mm brake rotor adapter, a steerer tube spacer set, and a boost axle spacer kit.

What is the advantage of the HS3 air spring system?

The HS3 system uses two positive air chambers working with a self-equalizing negative chamber. This allows independent tuning of initial bump compliance and mid-stroke support without making the fork harsh near bottom-out.