Dual mass wheel - what is it and how does it work?

As far back as the end of the XNUMXth century, most cars moving on the roads were equipped with a single-mass disc clutch. The change was driven by technological progress - new cars were simply expected to have more power, which in turn required more torque. As a result, this led to a loss of control over vibrations, which were transmitted not only to the rest of the propulsion system, but also to the working parts of the machines. The problem was solved thanks to an innovative design in which two flywheels rotating on a common axis replaced one rigid one, which obviously could not cope with the work of new drives. It all started with diesels, and to this day, every diesel coming off the assembly line is equipped with a dual-mass wheel. As far as petrol engines are concerned, according to manufacturers, this applies to the vast majority of new cars.

Springs that absorb vibrations

The dual-mass wheel is an integral part of the transmission. Its task is to dampen the vibrations that occur during engine operation. They are very diverse, which depends mainly on the currently achieved rotation speed. At low vibration levels with such a high force that the fixed parts of the drive can hit each other - this leads to their faster wear and can even cause serious failure. A double mass consisting of centrally located wheels that rotate independently and transfer energy to a spring system located around the circumference of one of them. The result is effective vibration damping and engine economy at low revs. By unloading the clutch, the dual-mass flywheel makes driving at lower speeds less stressful for the drive, which helps reduce fuel consumption while maintaining driving comfort. In addition to the dual-mass engine, this also saves the gearbox and other transmission components.

How does it work?

Contrary to appearances, the construction and operation of the breakthrough part is quite complex, although at first glance it looks like a traditional rigid flywheel. As the name suggests, they consist of two masses. The primary is attached to the crankshaft and performs a function similar to the traditional solution. The difference lies in the internal secondary mass on a common axle. Between the masses there is a torsional vibration damper connecting both disks, consisting of springs and flexible disks. This is where the stresses generated by the vibrations of the drive components are absorbed. Rings that move towards the axle can slide in both directions up to a quarter of their circumference.

Dual-mass wheel - how it differs from traditional parts

Dual mass wheels were built in response to the challenges of technological progress. If the giants of the car manufacturing market, such as Mercedes Benz, Toyota or BMW, have been assembling these parts in the factory for years, then we are dealing with an optimal solution that requires the correct operation of cars. The increase in power and torque has led to a decrease in the life of parts that are subject to constant wear during intensive driving. Most often this happens when the basic principles of smooth driving technique are not followed, which leads to excessive overloading of components, which can lead to progressive wear. When subsequent drivers find out that their Fiat, Ford or Subaru is in need of repair after a few years of operation, they cannot help but rejoice. When they hear that their “nearly new” car is about to be replaced not only by the mass flywheel, but also by the clutch, they look for alternative solutions. Moreover, the cost of a new set requires at least several thousand zlotys from your wallet. Therefore, we can find alternative solutions on the market.

Dual mass flywheel and rigid flywheel - can they be freely changed?

An interesting option is repair kits with a rigid flywheel instead of a movable one. Although the new technology has already become the accepted standard, its predecessor is still in the game, some manufacturers - especially in smaller cars - still do not use a dual-mass wheel. An example of such a car is the Toyota Yaris with a 1.4 D4D engine. When we look at the drive system of this city car, we find a rigid flywheel. In the minds of drivers who want to save on replacement costs, the idea may arise to weld on a tight-tapping (read damaged) dual-mass wheel. Since some modern diesel engines do not use dual masses, it is easy to conclude that they are not needed at all. However, this way of thinking is not rational. Since the engine with transmission is designed to dampen excessive torsional vibrations with a dual-mass flywheel, you should not change it yourself.

An exception may be specially designed kits for converting a dual-mass flywheel into a rigid single-mass flywheel with a special clutch disc that dampens engine vibrations.

Repair kits with single-mass wheel

Aftermarket leaders such as Valeo, Rymec, Aisin or Statim offer dual-mass to rigid wheel conversion kits for many cars and vans. Together with a full clutch (this is the only way to make an effective repair), their price can be up to 60% lower than the original dual mass flywheel. This is a popular solution to use when wallet condition is the deciding factor. The decision is "smart" not only because of the cost of the purchase. The assembly process is the same as for the dual mass flywheel kit. Therefore, no further transmission modifications are required. In addition, the double mass will not need to be replaced again in the future. The rigid wheel does not wear out. The only working element is a special clutch disc, the purchase and replacement of which is much cheaper than a complete set with a double mass. However, you need to know that although installing a hard drive will cope with the engine of the specific model for which it is intended, driving comfort will not be the same as when you are under the hood of a dual-mass engine. flywheel.

Change your driving habits - you don't have to think about changing

Want to avoid costly repairs? Whether you're using original parts, aftermarket parts, or a hard wheel conversion kit, using your vehicle properly can greatly extend the life of your drivetrain components. How to do it? The right driving style not only saves fuel, but can also decide whether primary and secondary mass consumption is so high that you have to visit car services. All you have to do is follow the four instructions below:

• Don't move too fast. Hard acceleration destroys the vibration dampers and the clutch disc.
• Do not accelerate from very low revs. Even a single episode with an overloaded wheel will have a significant impact on the drive control system.
• Keep this in mind when driving, especially in heavy traffic. Low speeds in high gears create the most uncontrollable vibrations.
• Use start and fire with the clutch depressed.

Dual mass wheel and chip tuning

The planned chip tuning is also a change in engine power. A common mistake is that it is applied without taking into account the efficiency of the transmission, which is likely to wear out faster when the car increases torque. And yet, the dual-mass flywheel has limited parameters of possible vibration overloads of the entire system. When tuning, the stock laid down by the designers is not enough, so during the frenzy with the tuned car, the two-mass springs will be subjected to a breaking load. This is another way to wear out all parts of the clutch and gearbox faster. When deciding to change the technical parameters of the car, it should be borne in mind that your car will need to repair the transmission system much faster. A small increase in power and torque, as well as judicious use of the car, should not hurt the double mass. However, a sharp increase in these parameters and the full use of the engine's capabilities in a short time will lead to the need to replace the dual-mass flywheel. If you're serious about tuning, we recommend replacing the dual-mass flywheel and clutch with components designed for sports applications, such as Exedy.

The article was written in cooperation with the online store sprzeglo.com.pl