The Fox DHX Factory [paid link] rear shock is a premium shock absorber designed for high-performance mountain bikes. Its advanced technology provides exceptional damping and adjustability for a smooth ride on rough trails. However, to maintain its performance and extend its lifespan, regular servicing is necessary. While taking your shock to a professional mechanic is always an option, you can also perform basic maintenance yourself with the right tools and knowledge. This guide will walk you through the process of servicing your DHX Factory [paid link] rear shock.
Tools Required
Before beginning, gather the following tools to ensure a smooth service process:
- 8mm, 10mm, and 12mm wrenches
- Torque wrench [paid link] (recommended torque values are critical)
- Suspension fluid (specific to Fox rear shocks)
- Air compressor or shock pump
- Oil drain pan or container
- Rags for cleaning
- Seal kit for DHX Factory shock
- Specialized shock oil (Fox Float Fluid)
- T25 and T30 torx drivers
- A clean workspace
Disassembling the DHX Factory Rear Shock
Step 1: Remove the Shock from the Bike
To start, you’ll need to remove the shock from your bike. Begin by using a 10mm wrench to remove the bolts securing the shock to the frame. Carefully set the shock aside once it is free from the mounting points.
Step 2: Drain the Air from the Shock
Using a shock pump, release the air pressure from the DHX Factory shock. This step is crucial for safely disassembling the shock, as it prevents any internal pressure from causing damage during the process. Once all air is released, you can proceed to the next step.
Step 3: Remove the Damper Cartridge
Use the appropriate torx driver (T25 or T30) to remove the screws that hold the damper cartridge in place. Carefully slide the damper out of the shock body. Be sure to keep track of any washers or spacers that may fall out during this step.
Step 4: Drain the Fluid
Place the shock over an oil drain pan or container and carefully remove the shock’s eyelet caps and seals. Drain the old fluid from the shock body. This is the time to inspect the oil for any contaminants or signs of wear. Old, dirty fluid can significantly degrade the performance of the shock.
Cleaning and Inspection
Step 1: Clean the Components
Thoroughly clean all parts, including the damper cartridge, air sleeve, and shock body. Use a clean rag to wipe off any dirt, grease, or old suspension fluid. Avoid using harsh solvents that might damage any rubber or plastic components.
Step 2: Inspect the Seals and Damper Cartridge
Check the seals for signs of wear or damage. Worn seals can cause leaks, leading to reduced performance. Also, inspect the damper cartridge for any visible signs of wear, such as scratches or dents. Replace the seals and cartridge if necessary.
Reassembly and Maintenance
Step 1: Install the New Seals
Use the new seals from the DHX Factory seal kit to replace any worn or damaged seals. Carefully install the new seals on the damper cartridge and air sleeve. Make sure that the seals are properly aligned and seated to avoid any leaks when the shock is reassembled.
Step 2: Fill with Suspension Fluid
Using the appropriate suspension fluid, fill the shock body and damper cartridge according to Fox’s specifications for the DHX Factory model. The right fluid level is essential for proper damping and overall shock performance. Use a syringe or a similar tool to avoid spilling fluid during this process.
Step 3: Reinstall the Damper Cartridge
Once the shock body is filled with fluid, carefully reinstall the damper cartridge. Make sure that it is aligned properly and securely tightened using a torque wrench [paid link]. Follow the manufacturer’s recommended torque values to ensure proper compression and performance.
Step 4: Reassemble the Shock
Once the damper cartridge is securely in place, reassemble the shock by replacing the eyelet caps and seals. Double-check that all components are correctly aligned and that there is no excess fluid leaking from the seals.
Charging the Shock
Step 1: Apply Air Pressure
Now that the shock is reassembled, use a shock pump to apply the recommended air pressure to the shock. The air pressure should match your rider weight and the type of terrain you will be riding on. Refer to Fox’s manual for the correct pressure settings for your DHX Factory rear shock.
Step 2: Check for Leaks
Before reinstalling the shock on your bike, check for any air leaks around the seals. Apply a small amount of soapy water around the shock body and seals. If bubbles form, it indicates a leak, and you may need to replace the seals again.
Reinstalling the Shock on the Bike
Step 1: Mount the Shock
Once you have confirmed there are no leaks, it’s time to reinstall the shock onto your bike. Carefully align the shock with the mounting points on the frame and tighten the bolts using the appropriate wrenches. Ensure that the bolts are tightened to the manufacturer’s recommended torque values.
Step 2: Set the Sag and Rebound
After reinstalling the shock, you will need to set the sag (the amount the shock compresses under your weight) and adjust the rebound settings. These adjustments will ensure optimal comfort and control. The sag setting is typically around 25-30% of the total shock travel, but this can vary depending on your preferences and riding style.
Troubleshooting Common Issues
Air Pressure Loss
If you notice that the shock loses air pressure over time, the seals may be worn or damaged. Inspect and replace any seals as needed. Additionally, check for any cracks in the shock body or air sleeve that may be causing the air to escape [paid link].
No Compression or Rebound Adjustment
If the compression or rebound adjustment doesn’t seem to be working properly, there may be an issue with the damper cartridge or the internal oil levels. Inspect the damper for damage, and ensure the fluid levels are correct.
Leaking Fluid
If you notice fluid leaking from the shock, it may indicate a damaged seal or overfilled fluid. Inspect the seals and replace them as needed. Make sure that the fluid level is within the recommended range.
Customizing the DHX Factory Rear Shock for Optimal Performance
While the DHX Factory rear shock comes with a range of adjustable settings, riders can optimize performance by fine-tuning their suspension. Consider experimenting with different rebound and compression settings to match your riding style and the terrain you ride on. Lower rebound speeds can be useful for faster descents, while higher speeds may improve control on technical climbs.
Additionally, adjusting the air pressure based on the rider’s weight and preferences can significantly impact the shock’s performance. A rider who prefers a plush feel may opt for slightly lower air pressure, while a rider seeking a stiffer shock may choose to increase the pressure.
Comparison with Similar Models
While the Fox DHX Factory rear shock is one of the top models for aggressive riders, there are several other shocks in the Fox lineup, such as the Float X2 and the DHX2. Compared to the DHX Factory, the Float X2 offers a lighter weight and slightly more advanced adjustability. However, the DHX Factory shock offers superior durability and performance for heavy-duty use on rugged [paid link] terrain.
Another competitor in this category is the RockShox Super Deluxe Coil Ultimate [paid link]. This shock offers a coil spring, which provides a different ride feel compared to the air spring found in the DHX Factory. Riders looking for a more consistent, plush ride may prefer the coil shock, while those seeking a lighter, air-sprung shock may favor the DHX Factory.
Compatibility with Other Drivetrain Components
The Fox DHX Factory rear shock is designed to work seamlessly with a wide range of drivetrain components. It’s essential to ensure that your shock’s travel and mounting hardware are compatible with your frame and suspension setup. Consult your bike’s manufacturer for specific compatibility information before purchasing or servicing your shock.
The DHX Factory shock pairs particularly well with high-performance bikes featuring advanced frames and drivetrains, offering excellent responsiveness and fine-tuned adjustability. It’s important to verify compatibility with your bike’s frame and other suspension components to avoid any issues with performance.
By following these steps, you can service your Fox DHX Factory rear shock with confidence. Regular maintenance will keep your shock performing at its best, ensuring a smooth and comfortable ride on any trail.