Motorcycle Wet Clutch – How It Works

Nothing is more annoying than setting off on your planned lovely motorcycle trip, perhaps heading somewhere new to explore, and the clutch begins to make strange noises or even stops working completely!

How Does A Motorcycle Wet Clutch Works?

The clutch on a motorcycle is the most crucial component. A wet clutch is standard on most modern motorcycles. It’s soaked in engine oil to keep it cool and reduce friction.

It performs the function of transferring power from the engine to the gearbox in order to spin the rear wheel. A wet clutch can be burned up. Especially if you’re an off-road biker.

A wet clutch is one that has been soaked in oil, as opposed to one that has no oil in its parts. It consists of a number of plates referred to as drive plates that are engaged in a basket to provide drive to the vehicle. A clutch basket is present that covers the series of discs.

The clutch basket has slots that fit into the notch on the end of each drive plate. To engage the cage, the pressure plate assembly, which includes the drive plates and discs, slides into it. Because the clutch basket is linked to the drive chain, this engages the vehicle in drive.

What Is The Importance Of Wet Clutches On Motorcycles?

Wet clutches are commonly found on motorcycles and dirt bikes. In contrast to dry clutches, the wet clutches are lubricated with oil.

This oil will help in reducing friction. Friction is very important in clutch operation. The bike can easily run because the friction and steel plates are separated. The light turns green, or the gate swings open. The plates squeeze together as you let go of the clutch lever.

Dynamic friction is determined by the transition from the friction and steel plates spinning independently to becoming locked together. Once the plates are locked together and spinning in unison, they are subject to static friction principles.

Oil Has A Significant Influence On Clutch Performance

Motor oil is essential in both dynamic and static friction cases. The formulation has an impact on the dynamic friction you feel, which is best described as a clutch feel.

Inconsistent, or “loose,” clutch feel can be caused by oils with incorrect frictional properties. This impairs your ability to confidently pull away from a red light without the bike cutting out, or to start quickly and capture the hole-shot in a race.

Once the clutch lever is fully depressed and you’re riding, the oil contributes to the holding power, or static friction, between the plates.

Oils with poor frictional properties can cause the plates to slip under certain conditions, resulting in lost power to the ground.

How Can You Differentiate Between A Wet And A Dry Clutch?

Wet clutches are common and can be found on most motorcycles. It prevents the clutch from collapsing on itself. Without the oil, the clutch cannot stay as cool, causing dry clutches to be noisier and wear out faster.

Wet Clutches

In recent years, wet clutches have surpassed dry clutches in popularity. There are several reasons for this because wet clutches, as opposed to dry clutches, are covered in engine oil, allowing the clutch plates to cool.

As a result, wet clutches can withstand more abuse than dry clutches. Another reason wet clutches are more popular is that they are quieter at idle, making them ideal for stop-and-go traffic.

Dry Clutches

Dry clutches are not commonly seen on street bikes, but they can be useful for racing because they reduce engine drag. A dry clutch serves the same purpose as a wet clutch. The only distinction between the two types of clutches is that the dry ones are not lubricated.

What Are Some Pros And Cons Of Using Wet Clutches?

Nowadays, wet clutches have become more popular than dry clutches. For a wet clutch, the quality of the oil is important as oils with poor frictional properties can cause inconsistent or sloppy clutch feel.

Pros of wet clutches

Because of the oil circulation, a wet clutch has less wear and tear. When compared to a dry clutch, it has a smoother engagement. Also, it can withstand slipping during the initial clutch take-off and is less expensive to produce. Wet clutch operation is quieter and produces less noise than dry clutch operation.

Cons of wet clutches

The presence of the clutch necessitates the circulation of oil. The engine loses some horsepower to the rear wheel due to clutch rotation in oil. Engine oil contains a mixture of clutch debris and hammer (an oil filter is fitted to avoid such problems).

What Are The Keys To Selecting The Right Oil For Wet-Clutch Applications?

The use of the proper oil ensures maximum clutch life as well as improved operation and performance. Oils with poor frictional properties can cause the plates to slip under certain conditions, resulting in lost power to the ground.

  • Before using assure that the oil meets the ISO frictional requirements.
  • Check that the oil can withstand high temperatures and oxidation.
  • Check that the oil has shear stability and that it controls foaming.
  • Use the oil with the recommended viscosity by the OEM.

It is commonly assumed that the use of synthetic oils causes excessive clutch slippage; however, extensive field and laboratory testing has proven that theory false. Synthetic-based oils perform exceptionally well, do not alter the frictional characteristics of a wet-clutch, and can even improve its performance and longevity.

Related questions

How long should a motorcycle clutch be expected to last?

It typically has a range of 30,000 – 100,000 km. If the clutch is not properly maintained and frequently slips, it may need to be replaced after only 5,000 miles (8,000 km). However, if you know how to handle it, experienced riders can ride for over 100,000 miles (160,000 km) on a factory original clutch.

Is it necessary to depress the clutch when braking on a motorcycle?

Riders should use the clutch before the brake when riding their motorcycle at low speeds. When riding at high speeds, the actions are diametrically opposed. In an emergency, riders should simultaneously apply the brake and pull the clutch.


If you want to enjoy the best experience of riding with wet clutches, you need to pay special attention to the quality of the oil. Using the best oil for a motorcycle or dirt bike wet clutch allows you to focus on riding rather than on unplanned maintenance.

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