Radflo 2.0 Hydraulic Bump Stop – 2", 3" or 4" Travel
5SB-001-00
The Radflo 2.0 Hydraulic Bump Stop is engineered to control the final inches of suspension compression in demanding off-road applications. Rather than acting as a hard mechanical stop, this hydraulic bump progressively increases damping force as shaft speed rises, helping absorb severe impacts before they are transferred into the chassis, suspension components, and occupants.
AAvailable with 2", 3", or 4" of travel, this hydraulic bump stop can be integrated into a wide range of suspension layouts used in rock crawlers, Ultra4 cars, prerunners, desert trucks, buggies, and trail rigs. Each unit is fully rebuildable, serviceable, and tunable, allowing it to be matched to vehicle weight, suspension geometry, terrain, and intended use.
Includes:
- (1) Radflo 2.0 Hydraulic Bump Stop
- Selected Travel Length: 2", 3", or 4"
Note: Sold individually. Bump can, mounting clamp, strike pad, and installation hardware are sold separately unless otherwise noted.
Specifications
| Specification | Details |
|---|---|
| Manufacturer | Radflo Suspension Technology |
| Product Type | Hydraulic Pinch-Mount Bump Stop |
| Body Diameter | 2.0" |
| Travel Options | 2", 3" or 4" |
| Shaft Diameter | 1.25" |
| Shaft Material | Mirror-Polished Alloy Steel |
| Shaft Finish | Chrome Plated |
| Body Material | SSID Alloy Steel Tube |
| Body Finish | Clear Cadmium Plated |
| Body Caps | CNC-Machined 6061 Aluminum |
| Body Cap Finish | Black Anodized |
| Rod Guide | CNC-Machined Bronze with PTFE Coating |
| Piston | Radflo Aluminum Freeflo® Racing Piston |
| Seal Design | Quad-Ring and Lip Seal Combination |
| Valving Type | Velocity-Sensitive Deflective Disc |
| Valving Adjustment | Self-Adjusting |
| Valving Tuning | Consumer or Factory Tunable |
| Oil | Radflo High-Temperature Foam-Resistant Suspension Fluid |
| Pressurization | Nitrogen Gas |
| Nitrogen Pressure | 200 PSI |
| Serviceability | Consumer or Factory Serviceable |
| Quantity | Sold Individually |
Fitment
Universal Fitment
Common Applications:
- Rock crawlers and rock bouncers
- Ultra4 race vehicles
- Prerunners and desert trucks
- Custom tube chassis buggies
- Trail rigs
- Long-travel suspension systems
- High-speed off-road vehicles
Fitment Notes:
- Designed for custom off-road suspension systems using a compatible pinch-mount bump can or clamp.
- Select travel length based on available packaging space, suspension travel, vehicle weight, and intended use.
- Verify bump stop body diameter and mounting system compatibility before ordering.
- Proper bump stop placement and engagement height must be established during suspension mockup.
- The bump stop should contact a flat, reinforced strike pad as squarely as possible.
- Cycle the suspension through full compression before final welding or mounting.
- Final tuning may be required to match vehicle weight, terrain, shock package, and suspension leverage.
- Professional installation and suspension tuning are recommended.
Tech Insight
What does a hydraulic bump stop do?
A hydraulic bump stop acts as a secondary shock absorber during the final portion of suspension compression. Instead of allowing the suspension to hit a hard stop, it progressively slows movement and absorbs impact energy before full bottom-out.
What is velocity-sensitive damping?
Velocity-sensitive damping means the bump stop generates more resistance as shaft speed increases. A slow suspension compression produces less damping force, while a hard landing or high-speed impact produces substantially more resistance.
Why use a hydraulic bump instead of a rubber bump stop?
A rubber bump stop mainly provides a physical limit to suspension travel. A hydraulic bump stop controls the rate at which the suspension reaches that limit, reducing peak impact loads and improving chassis stability during severe compression events.
How do I choose between 2", 3", and 4" travel?
Shorter travel options are easier to package and engage later in the compression cycle. Longer travel provides a broader damping zone and can begin controlling suspension movement earlier. Selection should be based on available space, suspension travel, vehicle weight, leverage ratio, and intended terrain.
Why is the 1.25" shaft important?
The large-diameter alloy steel shaft provides strength and resistance to bending under repeated high-load impacts. Its chrome-plated, mirror-polished surface also helps reduce seal wear and friction during operation.
What does the Freeflo® Racing Piston do?
The Radflo Freeflo® Racing Piston controls fluid movement through the bump stop and works with the deflective disc valving to create progressive, velocity-sensitive damping throughout the stroke.
Can these bump stops be rebuilt and tuned?
Yes. These units are designed to be rebuildable, serviceable, and tunable. Valving changes can be used to adjust compression resistance for different vehicle weights, suspension designs, terrain, and driving styles.
How should a hydraulic bump stop be positioned?
The bump should be aligned so the shaft contacts the center of a reinforced landing pad with minimal side load. The suspension must be cycled through full compression to verify tire, axle, shock, link, and chassis clearance before final mounting.
Why is bump stop tuning important?
A bump stop that is too soft may allow harsh bottoming, while one that is too stiff can upset the chassis or create a sharp impact. Proper tuning allows the bump to control the final suspension movement without making the vehicle unpredictable.
