The Marzocchi Bomber CR Trunnion [paid link] Rear Shock is a high-performance rear suspension component designed for mountain bikers seeking a combination of comfort, control, and durability. This shock is known for its innovative features and adaptability, making it suitable for aggressive trail riders, enduro enthusiasts, and riders who demand top-tier suspension performance. This guide provides a comprehensive look into the Bomber CR Trunnion [paid link] Rear Shock, detailing its installation, adjustment, maintenance, troubleshooting, and compatibility considerations.

Installation of the Bomber CR Trunnion Rear Shock

Installing the Bomber CR Trunnion Rear Shock requires precision to ensure optimal performance and safety. Follow these steps to install the shock correctly:

1. Prepare the Bike: Ensure that the bike is properly secured on a workstand. Remove any components that might interfere with the shock installation, such as the rear wheel.
2. Remove the Old Shock (if applicable): If replacing an existing shock, remove the mounting bolts holding the old shock in place. Gently slide the shock out of its mounting points.
3. Check Mounting Points: The Bomber CR Trunnion features a trunnion mount system. Make sure the mounting points on the frame are compatible with this system. Trunnion mounts use a set of bolts that attach directly to the frame, eliminating the need for a traditional eyelet shock.
4. Install the Bomber CR Trunnion: Slide the trunnion shock into the frame’s designated mounts. Secure the shock using the provided bolts. Tighten the bolts evenly, ensuring the shock is seated properly and securely fixed.
5. Check for Proper Clearance: Before fully tightening the bolts, check for any clearance issues. The shock should not interfere with other components like the frame or linkage.
6. Final Tightening: Once the shock is aligned and seated correctly, tighten the mounting bolts to the manufacturer’s specified torque settings. Use a torque wrench [paid link] to avoid over-tightening or under-tightening.

Adjustment of the Bomber CR Trunnion Rear Shock

The Bomber CR Trunnion Rear Shock offers a wide range of adjustments that allow riders to fine-tune the suspension to their specific needs. Proper adjustment enhances performance, comfort, and control, especially on challenging terrain.

1. Rebound Adjustment

The rebound adjustment controls how quickly the shock returns to its extended position after compression. To adjust the rebound:

• Turn the rebound knob located at the bottom of the shock.
• Clockwise to slow down the rebound.
• Counterclockwise to speed up the rebound.

Begin by setting the rebound to a neutral position (usually the mid-range) and adjust according to personal preference and trail conditions.

2. Compression Adjustment

The compression damping controls how the shock reacts to impacts and pedal strokes. There are typically two settings on the Bomber CR Trunnion: low-speed and high-speed compression.

• Low-speed compression adjusts how the shock behaves under slower, more gradual impacts.
• High-speed compression adjusts how the shock reacts to rapid impacts.

Adjust both the low-speed and high-speed compression to suit your riding style and terrain. Softer settings provide more comfort and absorption, while firmer settings offer better support during aggressive riding.

3. Sag Adjustment

Setting the correct sag (the amount the shock compresses under the rider’s weight) is crucial for ensuring optimal performance. To adjust sag:

• Use the air pressure adjuster to fine-tune the shock’s air spring.
• Refer to the rider’s weight and the manufacturer’s recommended air pressure range.
• Ideally, the shock should compress 25-30% of its total travel when the rider is on the bike.

Maintenance of the Bomber CR Trunnion Rear Shock

Routine maintenance is essential to keep the Bomber CR Trunnion Rear Shock functioning at its best and extending its lifespan.

1. Regular Cleaning

After every ride, clean the shock to remove dirt, mud, and debris that can accumulate on the shock body and seals. Use a soft brush and soapy water, followed by a rinse with clean water. Make sure to avoid using high-pressure water directly on the shock.

2. Inspecting the Seals

The seals are a crucial part of the shock’s performance. Check the seals for wear or damage during each cleaning session. Replace seals immediately if you notice any signs of leakage or wear.

3. Air Spring Maintenance

If the air pressure in the shock decreases over time, top it up to the recommended pressure using a shock pump. Over time, you may also need to rebuild the air spring and damping internals to keep performance at its peak [paid link]. Follow the manufacturer’s maintenance intervals for more extensive servicing.

4. Shock Oil Service

The Bomber CR Trunnion shock contains oil that should be changed periodically. Oil changes help maintain smooth performance and prevent premature wear of the shock internals. Consult the manufacturer’s manual for recommended service intervals.

Troubleshooting Common Set-Up Issues

If you encounter performance issues with the Bomber CR Trunnion Rear Shock, consider the following troubleshooting steps:

1. Shock Bottoming Out

If the shock bottoms out (i.e., reaches the end of its travel too frequently), check the following:

• Sag Adjustment: Ensure the sag is set correctly and the air pressure is sufficient for your weight.
• Compression Damping: Increase the compression settings to firm up the shock’s response to impacts.

2. Excessive Rebound

If the shock rebounds too quickly, causing a jarring effect, slow down the rebound by turning the knob clockwise.

3. No Rebound or Stiffness

If the shock feels excessively stiff or has no rebound, check for air or oil leaks. A lack of rebound may indicate an issue with the internal damper or seal failure.

Customization and Optimization for Better Performance

The Bomber CR Trunnion Rear Shock is highly customizable, allowing riders to tweak their set-up for specific needs. Here are some tips for optimizing its performance:

• Use a different spring rate: Depending on your weight and riding style, swapping to a different spring rate may improve the shock’s performance.
• Fine-tune rebound and compression: As mentioned earlier, adjusting the rebound and compression can make a significant difference in how the shock behaves on the trail.
• Choose the right air pressure: Experiment with different air pressures to find the ideal balance between comfort and support for your riding style.

Comparison with Similar Models

When compared to other rear shocks in the market, such as the Fox Float X2 or the RockShox Super Deluxe, the Bomber CR Trunnion stands out for its robust build and ease of adjustment. While the Fox and RockShox models are also excellent, the Bomber CR Trunnion often appeals to riders seeking a more affordable, straightforward shock without sacrificing performance. It also excels in high-impact situations due to its durability and performance in aggressive trail riding.

Compatibility with Other Drivetrain Components

The Bomber CR Trunnion Rear Shock is designed to work seamlessly with a variety of mountain bike drivetrains, including both 1x and 2x systems. Its trunnion mount system is compatible with most modern frames that support this type of shock, allowing for a stable connection to the frame without compromising the bike’s geometry or suspension performance.

Ensure that your frame is specifically designed for a trunnion shock. The shock is compatible with a wide range of mountain bike types, but frame clearance should be checked before installation to prevent issues with geometry or suspension behavior.