How To Adjust A Centrifugal Clutch? Easier Than You Think!

Are you experiencing issues with your centrifugal clutch? 

If you own a Go-Kart, understanding how to adjust a centrifugal clutch is essential for maintaining optimal performance.

Fortunately, this straightforward process can be done with just a few tools.

I will walk you through each step of adjusting this small component in this article.

By following my instructions, you can optimize your machine and ensure smooth operation. Without further ado, let’s begin! 

What Is A Centrifugal Clutch & When Do You Need To Adjust It?

how to adjust a centrifugal clutch

A centrifugal clutch is a type of clutch mechanism commonly used in small engine applications. It operates based on centrifugal force and can engage and disengage at specific speeds.

So how do Go-Kart clutches work? In a Go-Kart, these tiny but mighty parts utilize the engine’s rotational speed.

When the engine reaches a certain RPM (revolutions per minute), the centrifugal force generated causes the clutch shoes to move outward, making contact with the inside of the clutch drum.

How many RPM is normal depends on the type of clutches and engines.

This friction allows power to be transmitted from the engine to the driven components, enabling them to operate.

Centrifugal clutch modification becomes necessary in several situations, such as:  

  • Abnormal engagement speed: The engagement speed of a centrifugal clutch refers to the engine RPM at which it begins to transmit power to the driven components.

If the clutch engages too early or too late, it may cause issues with the engine’s performance or make it difficult to control the vehicle or equipment. 

In such cases, adjusting the centrifugal clutch system is necessary.

  • Slipping: If the clutch slips under load, meaning it fails to transfer power efficiently from the engine to the driven components, it can result in a loss of performance or acceleration.

This can happen due to worn clutch shoes or incorrect tension settings. Adjusting the clutch’s tension or replacing worn components can help resolve slipping issues.

  • Wear and tear: Over time, the components of a centrifugal clutch, such as the clutch shoes, springs, or bushings, can wear out.

This can lead to improper engagement, slipping, or other performance issues.

Adjusting or replacing these worn-out parts is necessary to maintain the clutch’s optimal functionality.

How To Adjust A Centrifugal Clutch: 2 Simple Methods

go kart clutch problems

When modifying centrifugal clutches, you can either adjust the clutch position on the engine crankshaft in case of a clutch disengagement or the clutch spring when one of the springs has worn out, causing the clutch to engage at idle speed.

As mentioned, adjusting this part is easier than you think. In case you don’t know where to start, follow my step by step guide below.

As a rule of thumb, ensure you have an allen key (for set screws) and a wrench (for crankshaft bolts) ready.

Adjusting The Clutch Position On The Crankshaft 

Maintaining proper alignment between the centrifugal clutch sprocket and the rear axle sprocket is essential to ensure efficient torque transfer.

Misalignment of both components may cause the chain to premature wear and hinder your clutch from transferring torque efficiently.

Signs of misalignment include centrifugal clutch engages at idle speed, slipping, and difficulty starting.

Here is how you can keep the centrifugal clutch sprocket and the rear axle sprocket perfectly parallel in a few simple steps: 

Step 1: Locate The Set Screws

Firstly, find the clutch’s set screws on your Go-Kart. In most cars, they can be found close to the clutch sprocket, with one secured against the crankshaft and the other against the key.

Once you’ve located these clutch components, start loosening them using an allen key (or hex key). In order to do that, turn the set screws counterclockwise.

Some mechanics would take them out completely, but I recommend just loosening them to save time.

Step 2: Loosen Or Remove The Crankshaft Bolt 

After you are done with the set screws, let’s deal with the crankshaft step by step. First, locate the crankshaft bolt using your Go-Kart’s user manual.

Usually, the bolt will run perpendicularly into the crankshaft.

Then, proceed to loosen the bolt by turning it counterclockwise.

Step 3: Adjust The Position Of The Centrifugal Clutch 

When both the set screws and the crankshaft bolt are loosened, slide the clutch across the crankshaft to align it.

A cost-effective trick to align both the front and rear axle sprockets is to use a straight and long object that can cover the distance between these clutch components, such as a metal ruler, rod, or key stock.

Ensure the front or rear sprocket is not tightly attached to the crankshaft and is free to move.

Place the key stock against the rear sprocket, as it provides a larger surface area and is easier to align.

Point the key stock towards the crankshaft and ensure that the front sprocket aligns with the key stock, with or without the chain attached.

Step 4: Reinstall The Set Screws And Crankshaft Bolt

Once aligned, tighten the bolts securing the front and rear sprockets. Use a wrench or socket set to ensure the set screws and bolts are tightened evenly and securely.

Take the go-kart for a test run to ensure the sprockets are aligned correctly. Pay attention to the Go-Kart’s performance and engine speed.

If you notice any issues with the engine speed or abnormal wear on the chain, recheck the alignment and make further adjustments if needed.

Modifying The Clutch Tensions Springs

The tension spring is within the clutch.

After being in operation for a while, Go-Kart springs can suffer from excessive wear and tear. That means its centrifugal clutch will engage at slower speeds.

When this happens, the first thing you should do is check your clutch for wear. If it is still usable, perform my detailed step to modify the clutch tension springs.

Since the method requires you to open the centrifugal clutch, it is more complicated and might take 2-3 hours to complete.

Step 1: Remove The Centrifugal Clutch From The Crankshaft 

To begin, detach the clutch from the crankshaft. This involves removing the Go-Kart chain from the master link and taking off the washer and bolt from the crankshaft.

Additionally, you need to loosen the clutch’s adjustment screws.

Once you complete these steps, the centrifugal clutch can be removed. Keep the washer and bolt aside for the time being.

Step 2: Disassemble The Clutch 

The next step is to disassemble the centrifugal clutch. Locate the snap ring near the front sprocket, and remove it. This will expose the inner clutch components.

Step 3: Adjust/Remove The Tension Springs 

Depending on the types of clutches your Go-Kart has, there might be various spring configurations. Common clutch systems can have 1, 2, or 3 springs.

  • 1-spring centrifugal clutch: For this type, you will see a long clutch spring connected on both ends, forming a circle.
  • 2-spring centrifugal clutch: This type has two shorter springs that connect two flywheels.
  • 3-spring centrifugal clutch: There are three springs connecting three flywheels to a pivot.

To adjust the spring tension, you can try several things. First, remove some coils to boost the spring force. This can be done with the help of cutting clippers.

If this doesn’t work, you may need to replace the factory springs with aftermarket springs.

Remember to choose ones with the correct dimensions and weight to be compatible with your centrifugal clutch.

Step 4: Rebuild & Reinstall The Centrifugal Clutch

Next, assemble the clutch components back together. Make sure that all of the internal components function well.

While at this step, give the clutch some drops of oil. All you have to do is apply lubrication around the centrifugal clutch bushing and clutch discs but avoid the ventilation hole.

This will ensure the Go-Kart’s optimal performance.

Step 5: Attach The Clutch To The Crankshaft

Finally, attach the clutch back to the crankshaft and install the washer and bolt. Tighten the set screws and ensure that every part returns to its place.

Since a Go-Kart’s tension springs are prone to wear and tear, they require adjustments over time. Thus, it is recommended to perform this process on a regular basis.


centrifugal clutch engages at idle

How To Tell If Centrifugal Clutch Is Bad?

Common signs of a bad centrifugal clutch include: 

  • The clutch engages at idle speed
  • A burning lining smell. A slipping centrifugal clutch may release excessive heat, leading to heat damage inside the clutch drum
  • Squeaky clutch pedal
  • Slow takeoffs

Why Is My Centrifugal Clutch Smoking? 

Excessive heat can cause the clutch components to smoke. This could occur if the clutch is subjected to excessive weight or is defective.

Overheating can also happen if the clutch is slipping, causing friction and generating extra heat.

How Much Horsepower Can A Centrifugal Clutch Handle?

This depends on the type of centrifugal clutch your Go-Kart has. The most common one is 13 HP centrifugal clutch, which can handle a maximum of 13 HP, just as the name states.

Wrapping Up

Now you know how to adjust a centrifugal clutch! The process is much easier than you might think with the right tools and instructions.

Whether you choose to adjust the clutch position on the crankshaft or modify the clutch’s tension springs, make sure you follow my steps to avoid any damage or safety hazards.

It is also recommended to regularly check and maintain the clutch to ensure its longevity and optimal Go-Kart’s performance.

By properly adjusting and maintaining your centrifugal clutch, you can enjoy smooth rides and avoid unnecessary repairs in the future.

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