How to Fix Stiff Suspension on a Bike

If you value a smooth ride and comfort when traversing different road surfaces, a healthy bike suspension is your best friend. When your bike’s suspension is working well, it absorbs impact from bumps and rough terrain, allowing the wheels to dampen the force from obstacles, moving up and down slightly for comfort. 

But what happens when your suspension is not working at its best? There’s nothing more unpleasant for a cyclist than having to feel every bump in the road. 

In this blog, we’ll look at ways that you can troubleshoot stiff suspension and fix your bike for a smoother ride without being able to feel every lump, bump, and stone.

What does your bike's suspension do?

Located at the front (“air forks”) and back of your bike (“rear shocks”), your suspension is designed to absorb shocks and impacts from uneven, debris-filled road surfaces. 

Your suspension helps you maintain control, traction, and comfort while riding. From tackling rough trails or navigating pothole-ridden roads, the suspension system minimises vibration and reduces strain on your arms and legs. 

Bike suspension works by compressing and rebounding in response to any bumps on the terrain, ensuring that your tyres stay in contact with the ground for better stability and handling. Suspension enhances performance and safety when properly adjusted, making your ride smoother and more efficient. 

Testing to see if your bike's suspension is stiff

Unsure if your bike’s suspension is stiff and rigid?  Try the bounce test on your bike by standing next to it and firmly pressing down onto the handlebars (for front suspension) or the saddle (for rear shock). When you release the pressure, observe how the suspension reacts — if it barely moves or doesn’t compress smoothly, it may be too stiff. 

Alternatively, another way to test for stiff suspension is to measure the “sag” of your bike. You can do this by wearing your usual riding gear and sitting on the bike normally. Ask someone to measure how much the suspension compresses from its fully extended position when you sit down (this is called the “sag”). Compare the sag percentage to the bike's recommended value (typically 20-30% for a mountain bike). Your suspension may be too stiff if there is little to no sag. 

Why is your bike suspension stiff?

If your suspension is stiff, let’s find out why. Stiff suspension is a common occurrence for cyclists, especially those who use their bike a lot. There are many reasons why your bike’s suspension may be stiff, including: 

• Incorrect air pressure or coil preload
• Dirt and debris buildup in suspension components
• Worn-out seals or lubrication issues
• Damaged or misaligned suspension parts.

If you suspect any of these reasons to be the cause behind your stiff suspension, bring your bike to your nearest Kwik Fit centre and get it properly diagnosed and repaired by the Fettle experts.

Adjusting your bike's suspension settings

If your bike’s suspension feels too stiff, adjusting the settings can make a huge difference in comfort and performance. The two main ways to adjust your suspension depend on the type of suspension you have — either air or coil:

1. Check and adjust air pressure (for air suspension)

On most modern bikes, the front (air forks) and back (rear shocks) suspension require a specific amount of air pressure based on your weight. You can use a shock pump to check the current pressure. This is not to be mistaken for a regular bike pump as it allows for precise adjustments. 

At this point, you’ll need to dig out your bike’s manual as you’ll need to look for your bike’s recommended PSI (pound per square inch) and adjust your air pressure accordingly. Lower air pressure makes the suspension softer. 

2. Adjust the preload (for coil suspension)

For a bike with coil suspension, preload controls how much tension is applied to the spring. Locate the preload adjustment knob or ring (usually found on top of the coil), then turn it anti-clockwise to reduce stiffness and allow for more suspension movement. Be cautious as too little preload can cause the suspension to bottom out on big impacts. 

Start by making minor adjustments and testing the bike after each tweak. If your suspension still feels too stiff after these changes, it may need a full service or replacement of worn-out components.

When to seek help for your suspension

After adjusting your bike’s suspension, you should look forward to whizzing down hills (safely) and without feeling every bump and stone at 20mph. But, if you feel no change, then perhaps it’s time to call on an expert. 

Depending on several factors — such as the weather and how often you ride your bike — you should get your bike serviced every three to six months. Your suspension deteriorates as more dirt and water get into the coils, shocks, and bearings, so it’s essential to keep these areas clean and get them checked regularly. 

How to maintain your suspension components

Maintenance is key to extending your suspension’s life expectancy. Follow these steps regularly to ensure a smooth ride: 

1. Clean your suspension, especially after a muddy trip, use a mild detergent and avoid using high pressure.
2. Lubricate moving parts with suspension-specific lubricant. Apply to your fork stanchions and shock seal before cycling the suspension a few times and wiping the excess off. 
3. Inspect your suspension for cracks, oil leaks, or dirt buildup around seals. Also, test for loose bushings and get them replaced if needed. 
4. Check the air pressure of your bike’s tyres, use a shock pump to maintain correct air pressure. 
5. Remember to get your bike serviced after a maximum of 100 hours riding. 

Fix your bike suspension with Fettle

The quality of your suspension is crucial to a smooth, enjoyable ride. Remember to keep your suspension clean, lubricated, and get it checked every 100 hours of riding. 

At Kwik Fit, we’ve teamed up with the experts at Fettle for all things bike, so you know that local, quality bike and e-bike care is close by. Find your nearest centre for great bike servicing, repairs, and assembly today.