EXT is proud to introduce the FERRO USD 36, specifically designed for e-motorbikes such as the Sur-ron.
With the growing worldwide popularity of electric dirt bikes, EXT saw the specific need for suspension capable of matching these vehicles’ potential and used their decades long know how to design and develop this upside down design suspension fork to take your e-moto to the next level!
With heat treated 36mm stanchions with superfinish surface treatment, 7000 series aluminum upper legs with 205mm travel and a dedicated triple clamp and EXT's HS3 technology, the FERRO has been designed for minimum friction, high stiffness and extreme durability.
HS3 TECHNOLOGY
The FERRO USD 36 fork utilizes HS3 technology, a unique hybrid air spring system that operates in the same fashion as the already renowned ERA V2 MTB fork as well as other high end Moto options. The two separate positive air chambers work in tandem with a high volume self-equalizing negative air chamber to provide unparalleled mid-stroke support around the dynamic sag position while simultaneously offering amazing sensitivity and bottom-out protection.
3 WAY-ADJUSTABLE
A high-flow 3-way adjustable hydraulic damper cartridge featuring an independent High/Low speed compression and Rebound adjustments sets the new standard in fork adjustability. This allows each rider to properly adjust the damping forces according to their individual riding style and weight. The possibilities to tailor the fork on your preferences have become unlimited.
SLIDING BUSHINGS
We evaluated every aspect of the bushing design to provide a low friction solution to improve smoothness and sensitivity while maintaining structural rigidity.
The new DU bushing material used in the FERRO USD 36 fork are sized to defined tolerances for each fork assembly to work in harmony with dedicated EXT oil. This guarantees zero stiction and super low dynamic friction properties even when combined with high side loads. The dedicated DU guiding system made with a specific superlong bushing overlap ensures the maximum guidance and the best torsional rigidity characteristics of the stanchions. Perfect alignment and excellent sliding are guaranteed by the wheel axle with double hexagonal head. This shape, associated with the double crown in 7075 aluminum, ensures maximum torsional rigidity.
NEW HIGH-FLOW CARTRIDGE
The new FERRO USD 36 inherits the best technologies from EXT's well-known ERA V2 and it optimizes them for the E-MX application by adopting an innovative radial floating shaft guide in the damper cartridge with a Superfinish surface treatment and new aeronautical seals, which takes the friction to the lowest possible level. EXT high-volume cartridge uses a high flow piston to generate control for your bike, an essential performance upgrade for spirited riding.
This large piston design provides the best damping control possible. The cartridge is also equipped with a bump valve design (HDRV –High Dynamic Response Valve) with 2 different shim stacks for mid and high speed and an Internal Floating Piston (IFP) guided and combined with a bespoke thrust bearing to enhance fast response and guidance. Our goal has always been to find a balance between all the internal cartridge pressures, and through a long development process we made possible the optimization of the internal forces reaching low values of hysteresis and no cavitation.
Features
- 36mm hard chromed steel stanchions (heat treated 42CrMo4) with Superfinish surface treatment
- Dedicated design triple clamp uppers machined from 7000 series aluminum
- HS3 air spring system: featuring twin positive air system ¬+ 1 large negative self-balancing air chamber, providing an optimum level of support through the entire travel range.
- Chromed steel air spring shaft with Superfinish surface treatment
- High-flow 3-way adjustable cartridge with independent High/Low speed compression and rebound adjustments
- External air pressure release valve system on both legs to normalize pressure with ambient environment.
- Twin hexagonal floating axle, boost compatible ?20mm for maximum torsional rigidity at the axle assembly
- Air spring and cartridge radial guide system with bespoke aeronautical seals (minimizing dynamic friction during side loading events)
- Large piston design for best in class damping control and separate IFP/coil energized compression valve
- No cavitation and low hysteresis
- Self-hydraulic cartridge bleeding
- Dedicated Mobile Sliding DU guiding system with super-long static overlap (for maximum guidance and best torsional rigidity). (CGB Continuously Guided Bushing system to increase stiffness)
- 205 mm of travel and a shorter 44 mm offset for increased stability
Weight: 4500 g (with axle and lube)
TRAVEL
200 mm
AVAILABLE WHEEL SIZE
– 19 inch with flat crown
– 21 inch with drop crown