EXT Racing ERA Fork Cartridge Kit

The EXT Racing ERA Fork Cartridge Kit brings elite Italian motorsport hydraulic damping and suspension engineering to the Sur-Ron electric dirt bike platform. Handcrafted in Vicenza, Italy, by Extreme Racing Shox (EXT)—legendary developers of World Rally Championship (WRC) and downhill racing suspension—the ERA cartridge replaces factory fork internals with competition-grade closed-cartridge damping technology.

Lightweight electric dirt bikes present a unique suspension challenge: weighing around 50–85 kg, they overwhelm standard mountain bike downhill forks with severe brake dive, chassis pitching, and oil cavitation. The EXT ERA cartridge solves these issues with high-flow piston architecture, proprietary low-friction seals, and a pressurized internal reservoir that separates damping fluid from air, completely preventing oil foaming during aggressive riding.

The ERA system features independent external clicker adjustments for High-Speed Compression (HSC), Low-Speed Compression (LSC), and Rebound Damping, allowing riders to tune plush small-bump sensitivity independently from bottom-out resistance on hard jump landings.

Hydraulic Physics & Anti-Cavitation: Standard open-bath forks allow oil and air to mix under rapid cycling, causing cavitation and sudden loss of damping. The ERA cartridge utilizes an internal floating piston (IFP) to keep high-viscosity-index racing fluid pressurized, ensuring consistent hydraulic resistance throughout long, grueling downhill runs.

Professional Setup & Installation: Suspension is a critical safety component. Professional installation by a certified motorcycle or suspension technician is strongly recommended. Cartridges must be vacuum-bled with EXT racing fluid to ensure zero air contamination. Set rider sag to 20%–25% of total travel before fine-tuning clickers.

Companion Upgrades: Pair the EXT ERA fork cartridge with a TB Electric Moto Pro rear shock, Warp 9 oversized 220mm floating front rotor, and a GritShift Pro Peg Brace for a balanced, race-ready chassis.

Frequently Asked Questions:

Q: What is the advantage of an EXT cartridge kit over replacing the entire fork? A: The ERA cartridge kit upgrades the internal hydraulic damping and spring assemblies within your existing stanchions, delivering elite Italian race damping at significant savings compared to full fork assemblies.

Q: How does EXT anti-cavitation technology improve suspension performance? A: Pressurized IFP damping circuits keep hydraulic fluid separated from air, preventing oil foaming and maintaining consistent damping during continuous rough riding.

Q: What adjustments are available on the EXT ERA cartridge? A: The cartridge features external clickers for High-Speed Compression, Low-Speed Compression, and Rebound Damping.

Q: How often should EXT suspension fluid be serviced? A: For aggressive trail riding and racing, lower leg bath oil should be changed every 50 hours, with a full cartridge overhaul recommended annually or every 100 hours.

Q: Is professional installation required? A: Yes. Vacuum-bleeding and precise oil height setting require specialized suspension tools and training.

Internal Floating Piston & Damping Consistency: The EXT ERA cartridge employs an internal floating piston (IFP) backed by high-pressure nitrogen to keep hydraulic fluid under constant pressure. This prevents micro-bubbles from forming during rapid rough terrain cycling, ensuring uniform compression and rebound damping throughout long downhill descents.

HS3 Hybrid Spring Technology & Mid-Stroke Dynamics: The ERA cartridge features EXT's proprietary HS3 hybrid spring architecture, combining an adjustable air spring with dual internal coil springs. This creates a uniquely supportive spring curve that provides plush initial sensitivity without diving through the mid-stroke under hard braking.