ST Coilovers ST XA galvanized steel (with damping adjustment) - BMW 1 Series F20 M140i

ST XA Coilovers – BMW 1 Series F20 M140i

The ST XA Coilovers for the BMW F20 M140i are designed for drivers looking for adjustable ride height and manually adjustable damping in a road-focused suspension package.

Sitting above the ST X in the range, the XA adds adjustable rebound damping, giving M140i owners more control over how the car responds on the road while retaining the everyday usability that makes the F20 such a strong all-round performance car.

Why choose ST XA for your BMW M140i?

The F20 M140i combines strong straight-line performance with a rear-wheel-drive chassis that responds well to suspension upgrades.

The ST XA gives you the ability to lower the car and fine-tune the damping to suit your preference, making it a strong choice for daily driving, fast-road use and more spirited setups.

Compared with a fixed-damping coilover, the adjustable rebound gives you greater flexibility to alter how controlled or compliant the car feels.

Key Features

• ST XA coilover suspension
• BMW F20 M140i application
• Adjustable ride height
• Adjustable rebound damping
• Road and fast-road focused setup
• Improved body control
• Vehicle-specific spring and damper tuning
• Galvanised steel damper construction
• Corrosion-resistant coating
• Developed using KW suspension technology
• Suitable for daily-driven performance cars
• Strong balance between comfort and handling

Adjustable Rebound Damping

The defining feature of the ST XA is its adjustable rebound damping.

Rebound controls how quickly the suspension extends again after being compressed.

Increasing rebound damping can provide stronger body control and a more settled feel during cornering, braking and directional changes.

Reducing rebound can allow the suspension to move more freely and provide greater compliance on rougher roads.

This gives M140i owners useful flexibility to tailor the suspension around driving style, road conditions and tyre choice.

Adjustable Ride Height

The ST XA allows the ride height of the BMW F20 M140i to be adjusted within the application-specific range.

This makes it possible to reduce arch gap, improve stance and lower the vehicle’s centre of gravity.

For road-driven cars, ride height should still be selected with suspension travel, tyre clearance and geometry in mind rather than simply setting the car as low as possible.

A full wheel alignment is strongly recommended after installation.

Galvanised Steel Construction

The ST XA uses galvanised steel damper bodies with a protective coating designed to resist corrosion.

This construction provides a durable and cost-effective alternative to the stainless-steel bodies found on KW INOX-LINE coilovers.

For cars used throughout the year, regular cleaning of the threaded adjustment areas is still recommended, particularly during winter when road salt and contamination can build up.

BMW F20 M140i Suspension Upgrade

The M140i responds well to chassis improvements, particularly when additional power or higher-grip tyres are introduced.

The ST XA can work well alongside upgrades such as:

• Performance tyres
• Uprated suspension bushes
• Adjustable suspension arms
• Chassis bracing
• Rear subframe upgrades
• Limited-slip differential
• Performance alignment settings

For fast-road cars, combining coilovers with a quality geometry setup can significantly improve steering response and overall chassis balance.

ST X vs ST XA

The ST X is the simpler option in the range, offering adjustable ride height with fixed damping.

The ST XA adds adjustable rebound damping, allowing the suspension response to be tailored more precisely to the driver and road conditions.

For owners who simply want a lower stance and improved handling, the ST X is a strong choice.

For drivers who want additional control over ride and chassis behaviour, the ST XA is the more flexible option.

ST XA vs KW V2

The ST XA and KW V2 both offer adjustable ride height and rebound damping, but they sit at different positions in their respective ranges.

The ST XA provides a strong performance-focused package at a more accessible price point, while the KW V2 uses KW’s premium INOX-LINE stainless-steel construction and sits higher in the overall product hierarchy.

For an owner looking for strong road performance and useful damping adjustment without moving into a higher-priced premium coilover, the ST XA is a compelling option.

Road & Fast-Road Use

The ST XA is particularly well suited to:

• Daily-driven M140i models
• Fast-road builds
• Cars with uprated tyres
• Owners wanting adjustable ride height
• Drivers who want damping adjustment without a track-focused setup

For regular circuit use or more advanced chassis tuning, a more sophisticated 2-way adjustable coilover may be more appropriate.

Electronic Damper Compatibility

Some BMW F20 M140i models are equipped with adaptive electronic dampers.

Where conventional coilovers replace the factory electronic dampers, the original adaptive damping function will no longer operate.

Depending on the exact vehicle and kit specification, an electronic damping cancellation solution may be required to prevent warning messages.

Please confirm the exact application before ordering if your M140i is equipped with adaptive suspension.

Professional Installation & Alignment

Professional installation is recommended for the ST XA.

Once fitted, the vehicle should receive a full four-wheel alignment so that toe, camber and other geometry settings can be checked following the change in ride height.

For fast-road builds, a more performance-oriented geometry setup can further improve steering response and tyre utilisation.

Maintenance

The threaded height-adjustment sections and spring platforms should be kept clean and inspected regularly.

This is particularly important on cars used throughout winter, where dirt, moisture and road salt can accumulate around the adjustment collars.

Regular cleaning and suitable preventative maintenance will help keep the suspension adjustable over the long term.

BMW F20 M140i Compatibility

This ST XA coilover kit is intended for applicable BMW F20 M140i models.

Exact fitment can vary depending on vehicle specification, axle loads and whether the car is equipped with electronic damping.

Please confirm your exact vehicle details before ordering.

If you're unsure which ST XA kit your M140i requires, contact us and we'll help identify the correct application.

What's Included?

The ST XA is supplied as a complete vehicle-specific coilover suspension system for the applicable BMW F20 M140i, including:

• ST XA dampers
• Vehicle-specific springs
• Height-adjustment components
• Rebound damping adjustment
• Relevant installation components

Exact contents can vary depending on the selected application.

Explore More BMW M140i Parts

Looking to improve your M140i further? Explore our range of BMW F20 M140i parts and upgrades, including suspension, handling, braking and performance products.

BMW F20 M140i Parts – Shop upgrades specifically for the BMW F20 M140i.

ST Suspension – Browse the complete range of ST Suspension products.

Coilovers – Explore coilover suspension from ST, KW and other leading manufacturers.