BC Racing BR RN Coilovers BMW 2 Series M235I F22 (5-Bolt) (14+) 5/9kg.mm

Key Features

• Pillowball top mounts
• Bearing mounted upper spring platform
• Camber adjustable top mounts (depending on model)
• Ride height adjustment separate to spring preload
• 30 way adjustable damping
• Monotube damper design
• Tapered bottom mount locking collar to prevent collar working loose
• Custom spring rates available
• All spare parts available with low lead times
• Dust boot to protect damper seals
• 1 year manufacturer warranty

Which kit is right for you?

Corner Weighting Adjustment

The lower spring platform of BC Racing coilovers is adjustable, enabling the car to be configured for corner weighting, thereby attaining optimal balance and ensuring maximum tyre efficiency.

It's crucial for the car to distribute equal weight on each tyre of an axle. This entails both front tyres bearing equal loading as well as both rears. Such equilibrium guarantees that both tyres contribute equally during cornering, enhancing overall grip, maximising cornering speed, and reducing lap times.

Optional assister springs are available for purchase, facilitating the adjustment of wheel droop within the unit to meet specific requirements.

Ride Height Adjustable

Ride height is determined by the placement of the coilover bottom mount. This mount can be adjusted along the damper body to provide a comprehensive range of adjustments.

Due to the ride height being determined by an adjustable bottom mount instead of the spring platform, you maintain complete damper travel irrespective of the chosen ride height setting.

Damping Adjustment

BR coilovers feature 30 way damping adjustment that combines both rebound and compression in one adjuster for simplicity and ease of use. This adjustable facility allows you to fine tune the vehicle to meet the relevant conditions.

By tweaking front and rear damping you can adjust the way the car handles. Increasing damping force on the rear relative to the front, for example, will start moving the vehicle into a more oversteer orientated stance.

If you want to go drag racing in a rear wheel drive car then you want the back of the car to squat off the line to maximise weight transfer to the rear and therefore onto the rear tyres. This maximises traction and helps prevent wheel spin. To achieve this you would soften the rear dampers to allow faster compression. If you had the rear dampers set to hard, as you might run the car on a race track, then the car would be less inclined to squat so traction would be reduced.

Conversely, if you want to go drifting and are finding it hard to break traction and are having problems with understeer then making the rear dampers harder will help reduce traction whilst making the front dampers softer will give greater front traction. This will make the rear of the car looser whilst minimising understeer thus altering the vehicles handling characteristics more towards drift than drag, road or track.

Pillowball Upper Mount

Many of the BC Racing BR coilovers come with pillowball upper mounts. The mount itself is made from aluminium alloy, anodised and then bead blasted to give a high quality, durable finish.

The pillowballs themselves are of Japanese manufacture and their solid nature eliminates any flex or play associated with the standard rubber mounts so improving response and handling.

Camber Adjustment

If its possible to include camber adjustment on your vehicle then the BC Racing coilovers automatically include camber adjustable aluminium pillowball top mounts. These feature the same high quality Japanese manufactured pillowball but give the added benefit of an adjustable top mount that allows camber to be set to suit your needs be it road, track or drift.

Corrosion Protection

The damper units feature black chromed steel construction, ensuring exceptional durability even in the harshest European winters. Aluminium components such as top mounts and locking collars are anodised, while steel lower mounts undergo an electrophoretic deposition process followed by powder coating.

To ensure the quality of the protective processes and maintain the highest standard of anti-corrosive properties, a random assortment of steel components including brackets, dampers, and screws undergo a salt spray test on a monthly basis.

Patented Concave Lower Locking Collar

Coilovers use a locking collar to prevent the bottom mount becoming loose. If the bottom mount becomes loose then the damper body can work its way down into the bottom mount so reducing ride height on that one corner which can lead to dangerous handling characteristics. This is a very common problem for coilovers in general.

BC Racing utilise an innovative and patented designed lower locking collar with a bevelled edge that seats into a corresponding bevel in the coilover bottom mount. This vastly increases the surface area that the locking collar works on and so prevents the common and dangerous problem of the locking collars working loose.

Pillowball Upper Mount

BC Racing dampers employ a sophisticated shim stack design and high-quality oil to consistently regulate the compression and rebound speed of the damper rod, even in the most extreme conditions.

As the vehicle traverses uneven terrain, the compression and rebound movements of the damper rod cause the oil to heat up. Inferior quality dampers utilise inexpensive oil, whose characteristics fluctuate with changing temperatures. It's crucial to use high-quality oil capable of maintaining consistent viscosity across a broad temperature range. Once the oil begins to degrade, its properties change, resulting in alterations to damping and subsequently affecting the vehicle's handling characteristics.

BC Racing ensures the use of only high-quality oil, thereby maintaining damping rates not only in the immediate term (such as during spirited drives on back roads or on the track) but also maximising long-term durability with oil that resists rapid degradation over time, significantly extending the operating life of the dampers.

Nitrogen Pressurised Dampers

When you work a damper hard on track or on high speed bumpy roads you can cause the oil to aerate and cavitation can occour. This causes foaming which effectively reduces the oils viscosity and so reduces the units damping effect. High quality oil goes a long way to help reduce this problem but BC Racing go one step further and pressurise the dampers with nitrogen.

The nitrogen exerts a pressure on a floating piston which in turn exerts a permanent pressure on the oil dramatically reducing aeration and so improving the consistency and quality of the damping. The pressurised nitrogen also adds an additional element of effective spring rate to the damper unit.