GP Suspension 25mm Cartridge Kit

For Harley-Davidson Baggers with 21" Front Wheels

End the Bagger Suspension Struggle

Tired of "hideous brake dive" that makes your bike "consistently bottom out on harsh bumps?" Fed up with forks that "always sucked" and leave you "wallowing over medium freeway bumps?" Stock bagger suspension frustrates riders with excessive front end dive during braking, harsh impacts that "knock your teeth together," and the feeling that your "front suspension can't hold you up."

GP Suspension eliminates these problems. Our precision-engineered kit delivers proper spring rates, enhanced damping control, and consistent performance - transforming your bike from wallowing and diving to confident and responsive.

Racetrack Innovation, Street Perfection

Our 25mm cartridge kit brings proven racetrack technology to the road—engineered to absorb every bump while delivering exceptional confidence and traction. This isn't an overly stiff race system; it's precision-tuned for optimal street performance, blending race-proven innovation with road-ready comfort.

Built entirely in Ventura, CA. We've never outsourced our machining or engineering—every component is wholly American-made.

What Sets Us Apart

Revolutionary Three-Valve Technology

Our advanced three-valve system delivers superior fluid control and pressure management compared to conventional two-valve designs.

The advantage: The base valve, working alongside rebound and compression valves, provides precise hydraulic flow modulation. This eliminates fluid cavitation and pressure spikes that cause harsh, inconsistent damping in lesser systems.

Real-world performance: Soft response during low-speed compression for comfort, ramping up effectively for heavy impacts like potholes or speed bumps. Your suspension adapts intelligently, maintaining traction by keeping tires consistently connected to the road.

Integrated Topout Spring Control

Integrated Topout Spring Technology eliminates harsh fork extension at full travel while maintaining critical tire-to-ground contact. This prevents the jarring impact typically experienced when forks reach maximum extension and ensures your tire stays planted for maximum traction and control—essential for both safety and performance in all riding conditions.

Progressive Bottom-Out Control

Advanced Bump Stop Technology provides progressive bottom-out control that prevents harsh compression impacts. Rather than a sudden, jarring stop, our system progressively controls compression at the end of travel, maintaining traction and rider confidence even when suspension reaches its limits—critical for aggressive riding and unexpected road obstacles.

Custom-Built for You

Every kit is tailor-made considering your weight, bike weight, and riding preferences. Whether you want buttery smooth cruising on bumpy roads or rail-like precision for track day abuse, we build your kit specifically for your needs.

Performance & Length Options

• Stock length: Travel increased from 100mm to 118mm (recommended with 12.8"-13.1" shocks)
• 2" over option: Travel increased from 100mm to 122mm (additional height provides more playful, responsive handling; recommended with 13.5"-14" shocks)

Note: Pipe modification or short-style pipe required for shock lengths exceeding 13.1"

Full Adjustability at Your Fingertips

Located conveniently on your new fork cap:

• 30 clicks of compression adjustment
• 30 clicks of rebound adjustment
• 12 turns of preload

Set it and forget it, or fine-tune between rides—we're always a call away for setup support.

Fitment & Installation

Compatible Models:

• CVO Road Glides 2014-2019 (OEM spec 21" front wheel)
• All baggers 2014-2024 running 21" front wheels

Installation Requirements:

• Upper tube modification required: Larger piston diameter needs additional clearance and OEM bottoming assembly removal
• Alternative: Purchase our pre-modified GP Suspension fork tubes

What's Included

Pricing includes custom spring set selected by our setup technician based on your riding information.

Transform your bagger's performance with suspension that puts a smile on your face.