What is a slipper clutch? How does a slipper clutch work?

What is a slipper clutch? When you are riding at high speeds and suddenly you encounter a sharp corner – the obvious reaction would be to slow down by applying the brakes and shifting in lower gear. But what if you have lesser time and you want to shift 2-3 gears at a time?

And when you do this, you do it at the cost of damaging the gear box and putting your safety at risk which arises due to engine braking force. As a mechanism to reduce these issues, Slipper Clutch (also known as back torque limiter clutch) was introduced. Slipper Clutch helps by allowing the clutch to partially slip until the engine speed matches your own speed.

What is a slipper clutch?

If you have ridden or if you own a high revving motorcycle, you must be aware of what is called engine braking, which causes negative engine torque during high-speed downshifts. Or in other words, when you’re speeding and you shift to lower gear and the bike feels like it’s being pulled back without the rider having to touch the brakes.

What is a slipper clutch

Some riders use engine braking to slow down, which actually reduces brake usage and the brakes last longer. However, it does strain the clutch plates a bit. But it can be dangerous if one doesn’t know how to use it or if there’s an accidental downshift.

This where the slipper clutch (or back-torque limiter) comes in. It is designed for bikes that are more performance oriented. Its sole aim is to reduce the effect of engine braking when the rider happens to decelerate.

The braking force is transmitted through the chain drive to the rear wheel causing it to shake or lose traction. The slipper clutch is designed to partially disengage or ‘slip’ when the rear wheel tries to drive the engine faster than it would under deceleration. In very simple terms, a slipper clutch disengages or ‘slips’ until the engine and wheel speeds are compatible.

See also  How much does a motorcycle weigh? Differen motorbike classes

A slipper clutch is welcomed by those into track riding as it allows aggressive deceleration without the wheel losing traction and it ensures the gearbox is not damaged while shifting a few gears at a time.

While slipper clutch sounds like a shorthand way of saying slip-assist, but they are actually different. A slip-assist clutch also does what a slipper clutch does but along with that, it also allows a lighter pull on the clutch lever.

Another important use of the slipper clutch is that it can also prevent a catastrophic rear wheel lockup in case of engine seizure.

How does a slipper clutch work?

The main difference between a slipper clutch and a normal clutch is the clutch hub. A slipper clutch assembly uses ramps to drive apart from the clutch plates and these ramps are built into the inner basket as well as the pressure plate. These ramps can slip or slide in the direction of the rotation of the wheel.

So, with this kind of advanced & complex arrangement, even if you downshift more than one or two gears at a time, the rear wheel won’t be able to over-rev the engine. In such scenarios, the ramps slide or slip over each other, pushing the pressure plate away from the clutch and thus avoiding engine over-revving, rear-wheel locking or hop.

In simple terms, a slipper clutch disengages or slips until the engine speed i.e. the engine RPM (revolutions per minute) matches the speed of the vehicle.

Advantages of a slipper clutch

There are several advantages that you can avail yourself of through a slipper clutch over a standard clutch. All of which are enlisted below –

  • Slipper clutch reduces sudden forces on the inside of the transmission and hence, reduces wear and tear on the transmission
  • Correctly installed slipper clutch improves performance.
  • It can prevent disastrous rear wheel lock up in case of engine seizure or transmission failure.
  • It also reduces work of suspension by absorbing engine braking force hence less bumpy ride while cornering.
  • The rider does not need to concentrate on clutch operation which allows him to concentrate on other things such as body posture, braking etc while cornering.
See also  Where does Maple Motors get their cars? Inside Maple Motors

What is a slipper clutch

Disadvantages of a slipper clutch

Well, not everything is good is excellent with a slipper clutch. While practically speaking, everything is extraordinary. But when you take disadvantages hypothetically, then there are a few disadvantages as well. All of which are given below –

  • It’s mechanically complex. Some slipper clutches are really complex to install and deal with (not many of them).
  • They are expensive (not against the saving they make by reducing wear and tear of transmission, less suspension movement and increased rider safety).
  • Sometimes you really need the engine braking force to slow down the bike (but how many times?) which can work against the concept and investment on slipper clutch.
  • Slipper clutch can’t give desired results if not adjusted according to requirements.

What are the parts of a slipper clutch?

A slipper clutch comprises several parts, including the clutch hub, clutch plates, pressure plate, and springs.

The clutch hub is connected to the crankshaft and rotates with it, while the pressure plate is connected to the clutch cable and can be pulled towards the hub to engage the clutch.

The clutch plates are sandwiched between the hub and the pressure plate and transmit power from the engine to the rear wheel.

The springs hold the plates together and provide the necessary pressure for the clutch to engage.

Why are slipper clutches used?

The slipper clutch has several benefits over traditional clutches, especially in high-performance motorcycles. Here are the details.

  • Improved control: The slipper clutch prevents the rear wheel from locking up, allowing the rider to maintain control during quick downshifts.
  • Reduced wear and tear: The controlled slippage of the clutch plates reduces the stress on the gearbox, resulting in less wear and tear on the bike.
  • Smoother ride: The slipper clutch engages and disengages the clutch smoothly, resulting in a smoother ride and less jerky gear shifts.
  • Faster lap times: In racing, the slipper clutch can help riders achieve faster lap times by allowing them to brake later and carry more speed through corners.
See also  How long is Bristol Motor Speedway? Bristol Motor history

Types of slipper clutches

There are three types of slipper clutches: Mechanical, Hydraulic, and Electromagnetic. Here are the details.

What is a slipper clutch

Mechanical slipper clutch

The mechanical slipper clutch uses a system of ramps and balls to achieve slip. When the engine braking torque is high, the balls are pushed up the ramps, forcing the clutch plates to slip against each other. This mechanism is simple and reliable but requires periodic maintenance to ensure the balls and ramps are clean and lubricated.

Hydraulic slipper clutch

The hydraulic slipper clutch uses a hydraulic piston to control the pressure on the clutch plates. When the engine braking torque is high, the piston moves forward, reducing the pressure on the plates and allowing them to slip against each other. This mechanism is more complex than the mechanical slipper clutch but more consistent and requires less maintenance.

Electromagnetic slipper clutch

The electromagnetic slipper clutch uses an electromagnetic coil to control the pressure on the clutch plates.

When the coil is energized, it creates a magnetic field that attracts the clutch plates, reducing their pressure and allowing them to slip.

This mechanism is the most advanced of the three but also the most complex and expensive.

Installation and Maintenance of Slipper Clutches

Installing a slipper clutch is a relatively straightforward process, but it requires some mechanical knowledge and experience. It involves disassembling the clutch assembly, installing the slipper clutch, and reassembling the parts. Following the manufacturer’s instructions and using the recommended tools and lubricants is important.

Maintaining a slipper clutch is essential to ensure optimal performance and longevity. This involves regular cleaning, lubrication, and inspection of the clutch assembly.

Any signs of wear or damage should be addressed promptly, and the parts should be replaced as necessary.

FAQs

Are slipper clutches only used in racing bikes?

No, slipper clutches are now commonly found in many high-performance street bikes as well. They are especially useful in bikes with high horsepower and torque output.

Can slipper clutches be retrofitted to older bikes?

In some cases, slipper clutches can be retrofitted to older bikes, but it is a complex and expensive process. It is best to consult a professional mechanic to determine if it is possible and practical for your bike.

Do slipper clutches require special maintenance?

Yes, slipper clutches require regular cleaning, lubrication, and inspection to ensure optimal performance and longevity. Failure to maintain a slipper clutch can result in reduced performance and even failure.

Above is information about What is a slipper clutch? that we have compiled. Hopefully, through the above content, you have a more detailed understanding of How does a slipper clutch work? Thank you for reading our post.

Related Posts

Leave a Reply

Your email address will not be published. Required fields are marked *