Bicycle FAQ's Are Bicycle Pedals Reverse Thread

Are Bicycle Pedals Reverse Thread

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Have you ever found yourself struggling to remove a stubborn pedal from your bicycle? You twist and turn, but it just won’t budge. Frustrating, isn’t it? Well, fear not, because we’re here to shed some light on this common dilemma. That’s right, we’re talking about bicycle pedals and the age-old question: are they reverse thread? Join us as we demystify this topic and provide you with the answers you’ve been searching for.

Are Bicycle Pedals Reverse Thread

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Are Bicycle Pedals Reverse Thread

Cycling enthusiasts often encounter the term “reverse thread” when it comes to bicycle pedals. This raises a common question: Are bicycle pedals reverse thread? The answer is a resounding yes. Bicycle pedals employ reverse threads, also known as left-hand threads, which means that they are tightened in the opposite direction compared to the standard right-hand thread. In this article, we will delve into the world of reverse thread bicycle pedals, exploring their purpose, how to identify them, and the advantages and disadvantages they offer.

What is Reverse Thread?

Let’s start by defining what reverse thread actually means. Reverse thread, as the name suggests, refers to a type of threading that is opposite to the standard right-hand thread. While a right-hand thread is tightened by rotating it clockwise, a reverse thread tightens when turned counterclockwise. In the context of bicycle pedals, this means that the left pedal has a reverse thread while the right pedal employs a regular right-hand thread.

How Reverse Threads Differ from Regular Threads

Reverse threads differ from regular threads not only in their rotational direction but also in their shape and design. The direction of rotation is the most obvious distinction, with reverse threads requiring an anticlockwise rotation to tighten and a clockwise rotation to loosen. Regular threads, on the other hand, utilize a clockwise rotation to tighten and an anticlockwise rotation to loosen.

Examples of Applications that Use Reverse Thread

Reverse threads can be found in various applications beyond bicycle pedals. One common example is gas cylinders, where the valve cap often features reverse threads. This is done to prevent accidental loosening caused by the rotational forces applied when tightening other components onto the cylinder. By using reverse threads, the gas cylinder valve cap remains securely fastened even when other components are tightened in a clockwise direction.

Why Reverse Thread is Used on Bicycle Pedals

So, why are reverse threads used specifically on bicycle pedals? The primary purpose of employing reverse threads is to prevent pedal loosening while riding. Due to the rotational forces and vibrations experienced during cycling, pedals have a natural tendency to unscrew themselves if they utilize regular right-hand threads on both sides. By implementing reverse threads on the left pedal, the rotational motion of the cycling action actually tightens the pedal, preventing it from coming loose while riding.

Purpose and Benefits of Using Reverse Thread on Pedals

The implementation of reverse thread on bicycle pedals offers several benefits. Firstly, it enhances safety by reducing the risk of pedal loosening, which could lead to accidents or falls. The reverse thread ensures that the pedals remain securely in place during intense cycling sessions, providing a reliable and stable platform for the rider’s feet. Secondly, using reverse thread on the left pedal helps prevent the pedal spindle from becoming unscrewed over time due to the pedal’s rotational forces. This increases the durability and lifespan of the pedal and ensures smoother and worry-free rides.

Common Types of Bicycle Pedal Threads

To understand the concept of reverse thread on bicycle pedals fully, it is essential to explore the different pedal thread standards commonly used in the cycling industry. The most prevalent standards include the 9/16″ x 20tpi, 1/2″ x 20tpi, and 9/16″ x 18tpi, each popular in various types of cycling disciplines and regions.

Overview of Different Pedal Thread Standards

The 9/16″ x 20tpi thread is the most widely used standard in modern cycling. It is commonly used in mountain bike pedals, road bike pedals, and other high-performance cycling platforms. The 1/2″ x 20tpi thread is often found on older bicycles, particularly those designed for city commuting or recreational riding. The 9/16″ x 18tpi thread is less common but can still be found on some older BMX or freestyle pedals.

Comparison of Left and Right Pedal Threads

As mentioned earlier, the left pedal utilizes reverse thread, typically in a 9/16″ x 20tpi configuration, while the right pedal employs a regular right-hand thread. This distinction is made to prevent confusion during installation since pedal threads are not interchangeable. Mixing up the threads would cause the pedals to loosen instead of tighten when rotated, compromising safety and ride quality.

Thread Sizes and Pitches Used in Bicycle Pedals

In addition to understanding the different thread standards, it is crucial to familiarize oneself with thread sizes and pitches. The size of a pedal thread refers to its diameter, while the pitch indicates the distance between each thread. The most common pedal thread size is 9/16″, but 1/2″ pedals can still be found on certain bikes. Regarding pitch, the tpi (threads per inch) measurement determines the number of threads within a one-inch length. The most typical pitch is 20tpi, although 18tpi is occasionally used.

How to Determine if Pedals are Reverse Thread

Identifying reverse threaded pedals is a key step in properly maintaining and servicing your bicycle. Fortunately, there are a few visual cues and techniques that can help you determine if your pedals employ reverse thread.

Identifying Reverse Threaded Pedals

A simple way to identify reverse threaded pedals is by looking for the letters “L” or “R” engraved on the spindle of each pedal. The “L” indicates the left pedal, which utilizes reverse thread, while the “R” signifies the right pedal with a regular right-hand thread. However, not all pedals feature such markings, particularly older or generic models. In this case, it is important to rely on other visual cues.

Visual Cues for Recognizing Reverse Thread

Reverse threaded pedals often utilize distinctive markings or color-coding to indicate their reverse thread direction. These visual cues serve as reminders during installation and removal processes. Common visual cues include a groove or notch on the axle or a colored end cap on the left pedal. By paying attention to these visual indicators, you can avoid potential confusion and ensure proper threading alignment.

Thread Direction and Rotation

In addition to visual cues, understanding the rotational direction of bicycle pedals can help identify reverse threaded pedals. When sitting on the bike and looking down at the pedals, the left pedal rotates counterclockwise to tighten, while the right pedal rotates clockwise. If your pedals adhere to this rotation pattern, it indicates that the left pedal is reverse threaded.

Are Bicycle Pedals Reverse Thread

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Tools Required for Removing Reverse Threaded Pedals

To remove reverse threaded pedals, you will need a specific set of tools. These tools will ensure a safe and effective removal process, enabling you to maintain and replace your pedals when necessary.

List of Essential Tools for Pedal Removal

The following tools are essential for removing reverse threaded pedals:

  1. Pedal Spanner/Wrench: A pedal spanner is a long-handled wrench specifically designed for removing bicycle pedals. It features a thin profile to fit between the crank arm and the pedal, providing sufficient leverage and torque.

  2. Adjustable Wrench: In some cases, an adjustable wrench can be used as an alternative to a pedal spanner. However, it is crucial to ensure that the wrench fits securely onto the pedal flats to prevent slipping and damage.

  3. Anti-Seize Compound: Applying an anti-seize compound or lubricant to the pedal threads before installation can make future removal easier. This compound helps prevent rust and corrosion, reducing the chances of pedals seizing in place.

Specialized Tools for Dealing with Reverse Thread

While a pedal spanner or adjustable wrench is sufficient for most pedal removals, certain specialized tools can assist in dealing with stubborn or seized pedals. These tools include extended leverage wrenches, pedal-specific socket wrenches, and pedal removal sockets.

Step-by-Step Guide on Removing Reverse Threaded Pedals

Now that we understand the tools required, let’s dive into the step-by-step process of removing reverse threaded pedals. Following these instructions will ensure a smooth and successful pedal removal experience.

Preparation and Safety Measures

Before starting the removal process, it is important to take certain precautions:

  1. Choose a Safe Working Area: Ensure that you have a clean, well-lit, and sturdy area to work on your bicycle. This will facilitate an easier and safer removal process.

  2. Set the Bike in a Secure Position: Place the bike in a stable position, either by mounting it on a repair stand, leaning it against a wall, or turning it upside down, supported by handlebars and seat. The choice of position depends on personal preference and access to the pedal area.

Step 1: Positioning the Bike

Position the bike crank arms parallel to the ground by rotating the pedal of the opposite side until the crank arm is level. This will provide better access to the pedals while ensuring stability.

Step 2: Applying Lubricant

Apply a small amount of anti-seize compound or lubricant onto the pedal threads. This will help reduce friction and make the removal process smoother. Be cautious not to apply too much, as excess lubricant can attract dirt and grime.

Step 3: Using the Proper Tool

Insert the pedal spanner or adjustable wrench onto the pedal flats, ensuring a secure fit. For reverse threaded pedals, turn the wrench or spanner counterclockwise (left) to loosen the pedal. Initially, the pedal may feel tight, but a few rotations in the opposite direction will break the initial resistance.

Step 4: Applying Force and Unscrewing the Pedal

With your foot securely on the opposite pedal, apply force to the wrench or spanner to loosen the reverse threaded pedal. The initial resistance may require additional effort, but once it breaks free, the pedal should unscrew relatively easily. Continue turning counterclockwise until the pedal detaches completely from the crank arm.

Step 5: Repeat for the Opposite Pedal

Once the first pedal is removed, repeat the process for the opposite pedal. The right pedal follows the standard clockwise tightening and counterclockwise loosening procedure. Remember to apply anti-seize compound or lubricant before installing the replacement pedals.

Are Bicycle Pedals Reverse Thread

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Tips for Removing Stubborn Pedals

Occasionally, pedals may become stubborn or seized due to factors such as rust, corrosion, or overtightening. In these cases, additional techniques can be employed to loosen the pedals and facilitate their removal.

Dealing with Stuck or Seized Pedals

If the pedals do not loosen despite applying force, try using a long-handled wrench or extending the handle of your pedal spanner with a piece of pipe for added leverage. The extra torque can help break the resistance and loosen the stuck or seized pedal. Applying gentle heat using a hairdryer or a heat gun can also assist in expanding the metal, facilitating easier removal.

Additional Techniques to Loosen Tight Pedals

For excessively tight pedals, you can use a specialized pedal removal socket or a heat gun to carefully warm the crank arm around the pedal spindle. The expanding metal due to heat combined with a proper fitting socket can help break the pedal free. Additionally, applying a penetrating lubricant, such as WD-40, and allowing it to soak into the pedal thread for a few hours before attempting removal may help loosen the tight grip.

Replacing Reverse Threaded Pedals

Once you have successfully removed the reverse threaded pedals, you may need to replace them with new pedals or reinstall the same pedals after maintenance. Here is a step-by-step guide on replacing reverse threaded pedals.

Step-by-Step Guide on Installing Reverse Threaded Pedals

  1. Ensure the crank arm threads and the pedal threads are clean and free from dirt, debris, or previous lubricant residue.

  2. Apply a small amount of anti-seize compound or bicycle-specific grease to the pedal threads. This will provide lubrication and prevent future corrosion or seizure.

  3. Identify the correct pedal for each side by referencing the markings, visual cues, or color coding. Remember that the right pedal employs a regular right-hand thread, while the left pedal uses a reverse thread.

  4. Start threading the pedals onto their respective crank arms by hand, ensuring they thread in smoothly without resistance. Turn them clockwise (right pedal) or counterclockwise (left pedal) until they can no longer be tightened by hand.

  5. Use a pedal spanner or adjustable wrench to further tighten each pedal until they are securely fastened to the crank arms. Apply sufficient force but avoid overtightening, as it can cause damage to the pedal threads or the crank arm.

  6. Check that both pedals are aligned straight and parallel to the ground, with no wobbling or looseness. If necessary, adjust the alignment by carefully loosening and retightening the pedals.

Ensuring Proper Tightening and Alignment

Proper tightening and alignment of pedals are crucial for safe and smooth rides. A loose pedal can cause discomfort, decrease power transfer efficiency, and potentially lead to damage or injuries. On the other hand, an overtightened pedal can strip the threads or make future removal difficult. By following the steps outlined above and using the correct tools, you can ensure optimal pedal installation with the correct level of tightness and alignment.

Are Bicycle Pedals Reverse Thread

Advantages of Using Reverse Thread on Pedals

We have discussed the purpose and benefits of using reverse thread on bicycle pedals briefly, but let’s delve deeper into the advantages it offers.

Potential Confusion and Compatibility Issues

Reverse threaded pedals can lead to confusion during pedal replacement or installation. If one is not aware of the reverse thread nature of the left pedal, attempting to thread it in the wrong direction may cause damage to the crank arm threads. Additionally, it is crucial to ensure compatibility between pedal threads and crank arm threads to avoid cross-threading and potential damage to both components.

Additional Complexity in Pedal Installation

The reverse thread on the left pedal adds a level of complexity during installation or removal, particularly for beginners or individuals not familiar with the concept. It requires extra attention to detail and careful identification of thread directions to ensure proper tightening and prevent cross-threading.

Disadvantages of Using Reverse Thread on Pedals

While there are numerous advantages to using reverse threaded pedals, it is important to also acknowledge the potential disadvantages that come with this design choice.

Additional Complexity in Pedal Installation

As mentioned earlier, the reverse thread on the left pedal can introduce an additional layer of complexity during installation, particularly for individuals without prior knowledge or experience with this threading system. This complexity can lead to mistakes, such as overtightening, cross-threading, or damaging the threads.

Potential Confusion and Compatibility Issues

The non-interchangeability of pedal threads due to reverse threading creates potential compatibility issues between pedals and crank arms. Incorrect installation or attempting to use a regular right-hand threaded pedal on the left side can result in damaged threads, rendering the crank arm and pedal unusable.

In conclusion, reverse thread bicycle pedals are indeed a standard in the cycling world. They play a vital role in ensuring pedal stability and preventing loosening during rides. By understanding the concept of reverse threading, identifying the correct pedals, and using the proper tools, cyclists can confidently maintain, replace, and install their pedals without confusion or complications. While there are some disadvantages in terms of complexity and potential compatibility issues, the advantages of using reverse thread on bicycle pedals outweigh the drawbacks. By adhering to best practices and following the recommended step-by-step procedures, cyclists can enjoy safe and reliable rides with their reverse threaded pedals.

Are Bicycle Pedals Reverse Thread

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