Sirris MAYHEM RACING F43 FORK FOR E-RIDE PRO SR
Turn your E-Ride Pro into an outright weapon
Sirris Suspension and Mayhem Racing teamed up to deliver a purpose-built, race-only suspension system that completely redefines what’s possible on a compact e-moto. This isn’t an upgrade—it’s a transformation.
Designed exclusively for elite riders chasing wins, this custom Sirris Pro MX race-only tune unlocks true big-bike performance on the E-Ride Pro SR. You get access to the race-proven R46 rear shock platform paired with a 230mm travel fork (826mm extended length)—a combination that simply doesn’t exist anywhere else for this class of bike.
The result? Two additional inches of ground clearance. Massive suspension authority. Total control at speed. From flat-out straights to deep whoops and send-it landings, this kit delivers the confidence and composure of a full-size race bike in a compact, ultra-aggressive e-moto package.
F43 Mayhem Racing Tune | Tool Free LSC | 230 mm Travel | E-Ride Pro
Weight Range
Sirris offers a single weight range for Mayhem Racing custom Pro MX Tune for E-Ride Pro SR. (Listed weight range is rider weight without riding gear on. 15 pounds of riding gear is calculated into the weight ranges)
140 lbs - 180 lbs (Medium = 4.4/4.0 springs)
Fork spring rates listed are left side/right side
FORK SPECS:
Architecture
Upside down fork
Travel
230 mm
Free length
826 mm
Fork Spacing
178 mm - allows for unlimited tire choice
Fork weight
4 kg per leg (driven by sturdy construction required for the forces and speeds encountered when pushing these bikes to their limits without compromising performance)
Stanchions
Ø43, high tensile steel with hard chrome
Outer tubes
Seamless 7050 aluminum, type 3 hard anodized coating
Drop outs
6061 aluminum, type 3 anodized coating
Brake mounting
• Sized for 220mm rotors, replaceable caliper mount brackets allow for caliper and wheel upgrades
• E-Ride Pro SR 220mm rotor brake bracket is included
Axle
• Custom ultra stiff, race-grade ultra-high tensile hard chromed axle increases steering precision and confidence
• E-Ride Pro SR wheel spacers included
Wheel size
Package designed for 19”/16” wheels, also compatible with 21” and 18” rear
Triple clamps
• Billet 6061 aluminum, type 2 anodized coating
• Black or blue color options
Steer tube
Seamless 7050 aluminum, type 2 anodized coating
Stem mount
4-bolt direct mount stem only
Top cap system
Motorcycle-style top cap allows for more consistent control over steering bearing tension
Damping
• Custom, Pro MX tune, developed in partnership with Mayhem Racing
• Symmetrical and adjustable closed cartridge with spring backed modified IFP
• High-flow pistons + fully tunable compression and rebound valving
• Dual oil circuits for optimum performance. Separating lubrication and damping oils allows us to further optimize high and low speed damping performance.
• Balanced load, race-ready, high performance. No matter how hard you ride or how many laps you take, our closed cartridge forks will never fade and will always feel predictable.
• Hydraulic bump stop is a hydraulic bottom out control system that gives you soft landings and max stroke even on the most aggressive impacts.
Damper bodies
Seamless 7050 aluminum, type 3 hard anodized coating providing high durability and scratch resistance to keep your ride in top condition.
Rebound
Dual side high tensile steel spring, adjustable
Adjusters
External tool-free compression, rebound adjustment
(rebound adjusted using tool)
Seals
NOK MX seals
Bushings
Daido MX bushings
Guards
High impact PP, 210-degree wraparound
REQUIRED SHOCK FITMENT MODIFICATIONS
This is a true race setup, and proper installation is part of the deal.
To fit the E-Ride Pro SR:
- A Mayhem Racing custom upper gooseneck adapter is required to fit the rear shock onto the frame
- Installation involves drilling the frame
- Clear guidelines are provided, and the process is straightforward
- All parts and hardware are included with the kit
- Optional step: If you want to use the larger bolt for bottom linkage, the stock linkage must be drilled to accept the new supplied larger bolt
- No modifications to the frame are needed for the front fork
These modifications are what allow this platform to exist—and they’re what separate a race-winning build from a bolt-on compromise.
REQUIRED HARDWARE KIT
Complete rear shock hardware kit and instructions available at Mayhem Racing.
EASY INSTALL
Watch the video to see the step-by-step procedure to install the gooseneck and R46 rear shock. Tools required are listed in the video description.
No shortcuts. No compromises. Just pure race performance.
If you’re racing to win—and you want the most advanced suspension ever put on an E-Ride Pro SR—this is it.
The Partnership
Sirris Suspension — Engineering & Manufacturing
Sirris designed and produced the race-spec fork and shock used in this build. That includes:
- The F43 fork (230mm travel / 826mm extended length)
- The R46 rear shock platform
- Internal valving and Pro MX race-only tune
- Component manufacturing, assembly, and quality control
Sirris’ responsibility is the suspension units themselves—their engineering, performance characteristics, and manufacturing integrity.
Mayhem Racing — Fitment Development & Installation Authority
Tim at Mayhem Racing led the development of the bike-side integration for the E-Ride Pro SR platform.
That includes:
- Defining geometry targets
- Determining required chassis modifications
- Designing the custom upper gooseneck adapter
- Establishing linkage changes and hardware spec
- Creating and owning all installation procedures and instructions
This system requires structural modifications to the E-Ride Pro SR chassis in order to achieve proper geometry, clearance, and race performance. Those modifications were developed, tested, and validated by Mayhem Racing.
For that reason, Mayhem Racing is the sole authority on installation instructions and chassis modification guidance.
Why Installation Is Owned by Mayhem Racing
This is not a bolt-on kit.
To achieve this level of race performance, the platform requires:
- A Mayhem Racing custom upper gooseneck adapter
- Frame drilling and precision shimming
- Drilling of the stock linkage to accept a larger bolt
- Geometry-specific setup procedures
These modifications fundamentally alter how the suspension integrates with the chassis.
Sirris does not manufacture the E-Ride Pro SR frame, does not control its tolerances, and does not oversee individual installations. Because of this:
- Sirris cannot validate third-party installation work
- Sirris cannot assume liability for improper installation
- Sirris does not publish or control chassis modification procedures
All installation instructions, fitment specifications, and geometry guidance are created, maintained, and supported by Mayhem Racing.
If you have questions about fitment, drilling procedures, adapters, hardware, torque specs, or chassis prep—contact Mayhem Racing directly.
Responsibility & Authenticity
We’re proud of this collaboration—and we want to be clear and transparent about it.
- Sirris stands behind the engineering and manufacturing of its fork and shock.
- Mayhem Racing stands behind the fitment design and installation process.
Both companies share a passion for innovation, rider progression, and building things that didn’t exist before.
Clarity matters.
This system performs at an elite level because it was developed intentionally, installed precisely, and ridden aggressively.
Proper installation is not optional—it is fundamental to safety and performance.
OWNER'S GUIDE
F43 and R46 Mayhem Racing suspension for E-Ride Pro SR.
SERVICE PARTS
F43 and R46 Mayhem Racing service parts available now.
