Understanding Pre-loading a Motorcycle Suspension and How to Do It
Adjusting the rear suspension of a motorcycle, a process known as pre-loading, is a critical step towards optimizing its performance and handling. This task, however, requires careful attention, precise techniques, and appropriate equipment. This guide aims to demystify the concept of suspension pre-loading, explain its importance, and provide a step-by-step procedure to achieve the right adjustment.
What is Pre-loading a Motorcycle Suspension?
Pre-loading a motorcycle suspension involves adjusting the rear shock or spring to the optimal range of operation within the suspension's travel. By changing the preload, you can influence how well the rear tire remains in contact with the pavement, which is crucial for stability and control, especially during high-speed maneuvers and when carrying additional load.
Why Pre-loaded Suspension is Important
When a motorcycle is not properly pre-loaded, it can exhibit undesirable behaviors such as a 'stepping out' of the rear when turning at high speeds, or 'wallowing' when the motorcycle is heavily loaded. The goal of pre-loading is to ensure the suspension operates effectively, contributing to a smoother and more controlled ride, regardless of the terrain or load.
How to Determine if Your Suspension Needs Adjustment
A simple test to determine if your motorcycle needs suspension pre-loading is to look for signs such as the rear end 'stepping out' during high-performance turns or 'wallowing' when the bike is heavily loaded. Additionally, you can use a test rod and the appropriate tool (such as a shock compressor) to measure the exact preload required.
Pre-loading Techniques
Pre-loading involves tightening or loosening the cap on the rear spring to adjust the preload. Tightening the cap makes the spring shorter and stiffer, increasing the preload. Conversely, loosening it makes the spring longer and softer, decreasing the preload. This adjustment directly impacts how the rear tire engages with the pavement and how the rear end behaves during maneuvers.
Effects of Pre-loading
The primary effect of pre-loading is to adjust the ride attitude, ensuring the motorcycle remains in control and doesn't 'bottom out' as easily. This adjustment is particularly significant when dealing with progressively wound springs, as it can lead to changes in damping characteristics.
Compressed Spring Simulation
Think of a motorcycle as a floating system where the motorcycle's weight compresses a spring, with the wheel at the bottom. The more weight the spring bears (e.g., a passenger), the more it will compress. This compression affects the handling and ride quality of the motorcycle. Pre-loading helps to offset the compression, effectively raising the connection point of the motorcycle to the top of the spring and correcting the ride attitude.
Proper Equipment and Techniques
Performing the pre-loading adjustment is a task that requires specific knowledge and tools. It is recommended to consult a reliable manual, such as 'Sportbike Suspension Tuning' by Trevitt, and find a skilled helper to assist you. Avoid relying on too many online resources, as guidance can be inconsistent and potentially harmful if misapplied.
Impact of Preloading on Ride Quality and Handling
Pre-loading has a significant impact on the ride quality and handling of a motorcycle. By adjusting the preload, you can ensure the rear tire remains in constant contact with the pavement, even during high-speed turns or over rough terrain. This adjustment helps in maintaining control and stability, especially in challenging driving conditions.
Quarry and Pre-loading
It is important to avoid using vague or insufficient guidance from sources like Quarry. Instead, seek detailed and accurate information from reputable manuals and experienced professionals. The correct approach and tools can make a significant difference in the performance and safety of your motorcycle.
Conclusion
Pre-loading a motorcycle suspension is a crucial aspect of maintaining optimal performance and safety. By adjusting the shock or spring preload, you can enhance the ride quality, stability, and handling of your motorcycle. This adjustment is accessible to competent DIY enthusiasts, provided they use the correct techniques and tools.