BMW F20 F21 F30 F31 LCI 120d 320d Diesel B47 Dual Twin Mass Flywheel Clutch Kit

BMW F20 F21 F30 F31 LCI 120d 320d Diesel B47 Dual Twin Mass Flywheel Clutch Kit is a complete drivetrain component set designed for modern BMW B47 family diesel engines. This set from the Flywheels and gears category ensures precise torque transmission and reduces torsional vibrations characteristic of diesel engines, which translates into stable, comfortable, and predictable drivetrain operation.

Specifications and technical data

• SKU: 8605090
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 8605090
• Substitutable numbers: 21208605090, 8605090, 21217641236 7641237 21217603849 21208631809, 7641236 7603849 8631809, ŁS
• Fuel type: Diesel
• Category: Flywheels & Flexplates

Purpose and compatibility with the B47 unit

The presented set is designed for use in BMW 1 Series F20/F21 and 3 Series F31 LCI models with the B47 diesel engine in 120d and 320d versions. The dual twin mass flywheel clutch design is adapted to the torque characteristics of the diesel unit, allowing for effective vibration damping and smooth power transmission to the gearbox.

Proper matching of the geometry of friction elements, damping springs, and surfaces interacting with the crankshaft and gearbox ensures that the set operates stably across the entire rev range, both during calm driving and dynamic acceleration.

Construction and operating characteristics of the dual twin mass flywheel clutch

The dual twin mass flywheel clutch in this set combines the function of a classic dual-mass flywheel with an advanced clutch system, which allows for even more effective separation of vibrations generated by the engine from the rest of the drivetrain. Thanks to this:

• the level of noise and vibration felt in the cabin is reduced,
• the refinement of the diesel unit at low and medium revs is improved,
• peak loads transmitted to the gearbox and half-shafts are reduced,
• the smoothness of starting and gear shifting is increased.

A set configured in this way from the Flywheels and gears category is particularly beneficial in daily use, where frequent starting, city driving, and variable loads require stable, predictable clutch operation.

Application in diesel engine vehicles

Diesel engines generate high torque from low revs, which places high demands on drivetrain components. The use of a dual twin mass flywheel clutch in B47 units allows for:

• better utilization of torque potential without overloading the gearbox,
• reduction of jerking during sudden acceleration or deceleration,
• stable operation when driving at low speeds in higher gears.

As a result, the driver experiences a more linear response to the accelerator pedal, and the entire drivetrain operates in a more predictable and comfortable manner, which is particularly important in cars used both on the highway and in city traffic.

Characteristics of the used product

The offered set is a used item, which means it has been dismantled and was previously operated in a vehicle. This type of solution is often chosen for repairs and upgrades when the priority is to maintain the original manufacturer's specification while optimizing costs. The used OEM component allows for maintaining factory fitment for a specific BMW model without the need for modifications or adaptations.

For many users of cars with the B47 engine, choosing an original, used drivetrain set is a reasonable compromise between quality and budget, especially in the case of structurally advanced components such as the dual twin mass flywheel clutch.

Technical support and selection of appropriate parts

If you are planning a comprehensive repair or upgrade of the drivetrain area in your BMW and need other elements from the same group, such as dual-mass flywheels, ring gears, or components interacting with the starter, check the available parts in the BMW Flywheels and gears category.

When planning modifications or light tuning of a diesel unit, it is worth considering the condition and characteristics of the drivetrain components – you will find more practical tips in the article The best used parts for tuning your car, which discusses how to consciously choose used components for projects based on diesel engines.

Additional arguments for choosing original, used elements instead of random replacements are provided by the guide 5 reasons why a used OEM part is a better choice than a replacement, describing the practical differences in fitment, durability, and comfort of operation.