How to Adjust OME BP-51 | Rebound, Compression & Pre-Load

How to Adjust Old Man Emu BP-51 Shocks

The Old Man Emu BP-51 suspension system is a premier choice for 4x4 owners looking for ultimate damping customization. With its advanced internal bypass technology, the BP-51 lets you adjust settings independently to perfectly match your terrain, load, and driving style.

Depending on your vehicle setup, there are two primary ways to tune the BP-51: adjusting the rebound and compression damping, and setting the coil spring pre-load.

Modifying compression and rebound settings allows you to fine-tune shock response to bumps and handling input, while adjusting pre-load controls vehicle ride height and balances additional accessory weight. Here is your step-by-step guide to dialing in your BP-51 shocks.

BP-51 Tuning: Rebound vs. Compression

First, it's essential to understand the functional difference between these two adjustments:

• Compression: Refers to how the shock absorber behaves when it compresses (e.g., hitting a bump or landing a jump).
  • Increasing Compression (Firmer): Improves high-speed stability and body-roll control, but feels stiffer over minor chatter.
  • Decreasing Compression (Softer): Delivers a plush, smooth ride over low-speed bumps, but can increase body roll during cornering.
• Rebound: Controls how quickly the shock extends back out after being compressed.
  • Increasing Rebound (Slower Return): Increases vehicle stability on severe dips, but can cause the suspension to "pack down" if set too tight.
  • Decreasing Rebound (Faster Return): Allows the tire to react faster over rapid washboard terrain, but can feel bouncy if undertuned.

Step-by-Step: How to Adjust Compression & Rebound

Follow these steps to adjust your BP-51 damping dials:

1. Locate the Adjusters: The BP-51 features independent adjustment dials located directly on the shock body or reservoir base.
2. Identify Baseline Numbers: Note your current dial numbers (1 to 10 scale) so you have a reference point to revert back to if needed.
3. Make Your Adjustments:
   • Compression: Turn Right (Clockwise) to increase damping (firmer) | Turn Left (Counter-Clockwise) to decrease damping (softer).
   • Rebound: Turn Right (Clockwise) to slow down extension (firmer) | Turn Left (Counter-Clockwise) to speed up extension (softer).
4. Test Drive & Fine-Tune: Take your rig over a familiar test section to evaluate handling before making further 1–2 click adjustments.

Pro Tuning Tips:

• Start with Factory Recommended Baselines: Refer to the OME application guide for initial settings based on your vehicle model.
• Make Incremental Adjustments: Adjust 1 to 2 clicks at a time to clearly feel the change in dynamics.

BP-51 Pre-Load Adjustment

Adjusting the pre-load ring allows you to fine-tune front ride height and compensate for added weight like heavy steel bumpers, winches, or dual battery setups without changing the coil spring itself.

How to Adjust Pre-Load (Coilover Struts)

1. Mount the coilover into a professional spring compressor using OME tool #VM80020001.
2. Compress the coil spring until pressure is relieved from the threaded pre-load collar.
3. Loosen the pinch bolt using a 5mm Allen key.
4. Rotate the spring seat collar to your target height/setting.
5. Ensure the collar split does NOT align directly with the hose fitting.
6. Torque the pinch bolt back to 11 ft-lbs.
7. Decompress the spring carefully while maintaining eyelet alignment.

IMPORTANT: Pre-load adjustments require specialized spring compressor tools. It is strongly recommended to have a professional 4x4 suspension shop perform pre-load height changes.