1. Introduction
This manual provides essential information for the installation, operation, and maintenance of your Ohlins STX 36 Blackline Twin Shock Absorbers, model HD-751. These high-performance shock absorbers are designed to enhance the ride quality and handling of compatible Harley-Davidson Sportster models. Please read this manual thoroughly before installation and use to ensure proper function and safety.
2. Product Compatibility
The Ohlins STX 36 Blackline Twin Shock HD-751 is suitable for the following Harley-Davidson Sportster models:
- Harley-Davidson Sportster XLH 883 (XL-2) 1992
- Harley-Davidson Sportster XLH 1200 (XL-2) 1993
- Harley-Davidson Sportster XLH 883 (XL-2) 1998
- Harley-Davidson Sportster XL 1200 C (XL1) 1999
- Harley-Davidson Sportster XLH 1200 (XL-2) 1999
- Harley-Davidson Sportster XLH 883 (XL1) 1999
- Harley-Davidson Sportster XL 883 (XL1) 2000
- Harley-Davidson Sportster XL 1200 C (XL1) 2003
- Harley-Davidson Sportster XL 883 (XL1) 2003
- Harley-Davidson Sportster XLH 883 (XL1) 2005
- Harley-Davidson Sportster XL 1200 X Forty-Eight 2010
- Harley-Davidson Sportster XL 1200 C (XL2) 2011
- Harley-Davidson Sportster XL 883L Superlow (XL2) 2011
- Harley-Davidson Sportster XL 1200V Seventy Two (XL2) 2012
- Harley-Davidson Sportster XL 1200 CA (XL2) 2013
- Harley-Davidson Sportster XL 1200 CB Custom Limited B (XL2) 2013
- Harley-Davidson Sportster XL 1200 C (XL2) 2016
- Harley-Davidson Sportster XL 1200 CA (XL2) 2016
- Harley-Davidson Sportster XL 1200V Seventy Two (XL2) 2016
- Harley-Davidson Sportster XL 1200 C Custom (XL2) 2017
- Harley-Davidson Sportster XL 1200 T Superlow (XL2) 2017
- Harley-Davidson Sportster XL 1200 C Custom (XL2) 2018
- Harley-Davidson Sportster XL 1200 CB Custom Limited B (XL2) 2018
- Harley-Davidson Sportster XL 1200 T Superlow (XL2) 2018
- Harley-Davidson Sportster XL 1200 X Forty-Eight 2018
- Harley-Davidson Sportster XL 1200 XS Forty-Eight Special 2018
- Harley-Davidson Sportster XL 883L Superlow (XL2) 2018
- Harley-Davidson Sportster XL 1200 XS Forty-Eight Special 2019
3. Product Features and Technical Data
The Ohlins STX 36 Blackline Twin Shock HD-751 is a high-quality suspension component designed for optimal performance. Key features and technical specifications are detailed below:
Figure 3.1: A pair of Ohlins STX 36 Blackline Twin Shock Absorbers, showcasing their black finish and coil-over design. These are the primary components for rear suspension.
- Product Family: STX 36 Blackline Twin Shock HD 751
- Item Number: HD-751
- Type Code: S36D
- Design: Single Tube
- Piston Diameter: 36mm
- Shock Absorber Type: Monotube high pressure gas type with internal container in the main body.
Technical Data:
| Specification | Value |
|---|---|
| Length | 296mm |
| Stroke Length | 59mm |
| Spring Rate (N/mm) | 19 N/mm |
| Position | Rear |
| Assembled Spring | 00281-72 |
| Packing Unit | Pair |
Figure 3.2: A detailed view of the Ohlins shock absorber, highlighting the precision engineering and the distinct Ohlins branding on the component.
4. Setup and Installation
Proper installation is crucial for the performance and safety of your Ohlins shock absorbers. It is highly recommended that installation be performed by a qualified motorcycle technician. Incorrect installation can lead to damage to the product or the motorcycle, and may compromise rider safety.
General Installation Guidelines:
- Preparation: Ensure the motorcycle is securely supported on a stand, with the rear wheel off the ground.
- Removal of Old Shocks: Carefully remove the existing rear shock absorbers, noting the orientation and any spacers.
- Installation of New Shocks: Install the Ohlins STX 36 Blackline Twin Shocks. Ensure all mounting bolts are torqued to the motorcycle manufacturer's specifications. Do not overtighten.
- Clearance Check: Verify that there is adequate clearance around the shock absorbers throughout the full range of suspension travel.
- Initial Adjustment: While these shocks come pre-set, minor adjustments may be necessary based on rider weight and riding style. Refer to the motorcycle's service manual for general suspension setup principles.
Note: Specific torque values and detailed installation steps for your motorcycle model should be obtained from the official Harley-Davidson service manual.
Figure 4.1: Another perspective of the Ohlins STX 36 Blackline Twin Shock Absorbers, illustrating their compact design and robust construction, ready for installation.
5. Operating Principles
The Ohlins STX 36 Blackline Twin Shocks are designed to provide superior damping and control. As monotube high-pressure gas type shock absorbers, they utilize an internal container within the main body to separate the oil from the gas, preventing cavitation and ensuring consistent damping performance under various conditions.
The 36mm piston diameter contributes to effective oil displacement, allowing for precise control over compression and rebound damping. The pre-set spring rate of 19 N/mm is optimized for the specified Harley-Davidson Sportster models, offering a balanced ride for typical use.
While these shocks are designed for performance, it is important to ride responsibly and within the limits of your motorcycle and riding conditions. Always wear appropriate safety gear.
6. Maintenance
Regular maintenance extends the lifespan and ensures the optimal performance of your Ohlins shock absorbers. While Ohlins products are built for durability, periodic checks are recommended.
Recommended Maintenance Practices:
- Regular Cleaning: Keep the shock absorbers clean from dirt, grime, and road debris. Use mild soap and water, then rinse thoroughly. Avoid high-pressure washers directly on seals.
- Inspect for Leaks: Periodically check for any signs of oil leakage around the seals. A small film of oil is normal, but excessive leakage indicates a problem.
- Check Mounting Bolts: Ensure all mounting bolts are secure and torqued to specification. Loose bolts can lead to premature wear or failure.
- Inspect Bushings: Check the condition of the mounting bushings for wear or cracking. Worn bushings can affect handling.
- Professional Service: For internal servicing, re-valving, or major repairs, always consult an authorized Ohlins service center or a qualified suspension specialist. Do not attempt to disassemble the shock absorber yourself, as it contains high-pressure gas.
7. Troubleshooting
This section addresses common issues that may arise with shock absorbers. For complex problems, professional assistance is advised.
| Problem | Possible Cause | Solution |
|---|---|---|
| Excessive Bounciness / Poor Damping | Worn internal components, low gas pressure, incorrect spring rate for load. | Inspect for leaks. If no leaks, professional service may be required to check internal components and gas pressure. Ensure correct spring for application. |
| Harsh Ride / Lack of Compliance | Incorrect spring rate (too stiff), binding in suspension linkage (if applicable). | Verify spring rate is appropriate for rider/load. Check motorcycle's swingarm pivot and linkage for free movement. |
| Oil Leakage | Damaged oil seal. | Contact an authorized Ohlins service center for seal replacement. Do not ride with leaking shocks. |
| Unusual Noises (e.g., clunking) | Loose mounting bolts, worn bushings, internal damage. | Check all mounting bolts for proper torque. Inspect bushings for wear. If noises persist, seek professional inspection. |
8. Specifications
Detailed specifications for the Ohlins STX 36 Blackline Twin Shock HD-751:
- Manufacturer: OHLINS
- Item Model Number: HD751
- Manufacturer Part Number: HD751
- ASIN: B01IF0VG5O
- Position: Rear
- Material: Metal
- Item Weight: 3.67 Kilograms
- Package Dimensions: 59.4 x 23.2 x 18.4 cm
- Assembly Required: No
- Style: Classic
- Vehicle Service Type: Motorcycle
- Date First Available: 2 May 2018
9. Warranty and Support
Ohlins products are manufactured to high standards of quality and performance. For specific warranty information, please refer to the warranty documentation provided with your purchase or visit the official Ohlins website. Keep your proof of purchase for any warranty claims.
For technical support, service, or genuine Ohlins spare parts, please contact an authorized Ohlins dealer or service center. Using non-genuine parts may void your warranty and compromise performance and safety.
You can find more information and support resources on the official Ohlins website.
