Getting the right pedal wrench size is crucial for any cyclist, whether you’re performing routine maintenance like greasing the threads with Phil Wood products or swapping out your pedals for a fresh set from Shimano. A standard pedal wrench often measures 15mm, a common attribute, but pedal wrench size can vary slightly, especially on older or European models like those favored by Campagnolo. Using the wrong size wrench can damage the pedal axle or crank arm, making a simple task much more difficult, therefore, understanding the correct tool is fundamental.
Finding the Perfect Pedal Wrench Size: A Comprehensive Guide
Choosing the right pedal wrench can be surprisingly tricky. While it seems straightforward, using the wrong size can easily damage your pedals or crank arms, leading to costly repairs. This guide will walk you through everything you need to know to select the perfect wrench, ensuring smooth pedal removal and installation.
Why Pedal Wrench Size Matters
The most common mistake is using an adjustable wrench or a standard open-end wrench. These tools often slip, rounding off the pedal axle flats. A pedal wrench is specifically designed with a longer handle for leverage and a precise, thin profile to fit snugly between the pedal and the crank arm.
Using the correct size ensures:
- Secure Grip: Prevents slippage and damage to pedal flats.
- Optimal Leverage: Makes removing even stubborn pedals easier.
- Clearance: Thin profile allows access in tight spaces.
Identifying Your Pedal Wrench Size
The vast majority of bicycle pedals use one of two wrench sizes: 15mm or 8mm (hex wrench, also known as Allen wrench).
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15mm Wrench: This is the most common size for the flats on the pedal axle. If you see flats on the pedal axle where a wrench can grip, it’s highly likely you need a 15mm pedal wrench.
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8mm Hex Wrench (Allen Wrench): Some pedals, especially clipless models, don’t have external flats. Instead, they feature a recessed hex socket on the inside of the pedal axle where it meets the crank arm. This requires an 8mm hex wrench for removal and installation.
How to determine which size you need? Here’s a step-by-step approach:
- Visually Inspect the Pedal Axle: Look for flats on the axle where a wrench would attach.
- Check for a Hex Socket: If there are no flats, look for a recessed hexagonal hole on the inside of the pedal axle.
- Refer to the Pedal Manufacturer’s Specifications: If you’re unsure, consult the pedal manufacturer’s website or the documentation that came with your pedals.
Different Types of Pedal Wrenches
While the size is crucial, the type of wrench also matters:
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Standard Pedal Wrench: A long-handled wrench with a 15mm opening. These are the most common and provide excellent leverage.
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Combination Wrench: Some wrenches offer both a 15mm pedal wrench opening on one end and another size (often 14mm or another hex size) on the other.
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Hex Wrench (Allen Wrench) Sets: Essential if your pedals use a hex socket. Ensure your set includes an 8mm wrench. Higher quality sets often have ball-end hex wrenches which can be very useful when working in tight spaces.
Factors to Consider When Choosing a Pedal Wrench
Beyond size, keep these factors in mind:
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Length: A longer handle provides more leverage, making stubborn pedals easier to remove.
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Material: Chrome vanadium steel is a durable and reliable material.
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Comfort: Some wrenches have ergonomic handles for a more comfortable grip.
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Price: Pedal wrenches range in price, with higher-priced models often offering better quality and durability.
Troubleshooting Pedal Removal Problems
Even with the correct wrench size, you might encounter difficulty removing pedals. Here are some common issues and solutions:
- Tight Pedals: Apply penetrating oil (like PB Blaster) to the threads and let it soak for a few minutes.
- Incorrect Direction: Remember that the left pedal (non-drive side) has a reverse thread. This means you loosen it by turning it clockwise. The right pedal loosens by turning it counter-clockwise – the standard way. A helpful rule of thumb is to always try to loosen the pedal towards the back of the bike.
- Damaged Flats: If the flats are rounded off, you may need a specialized tool designed to grip rounded surfaces. In severe cases, a professional mechanic might be required.
Common Pedal Wrench Sizes By Pedal Type
| Pedal Type | Wrench Size | Notes |
|---|---|---|
| Most Flat Pedals | 15mm | External flats on the axle. |
| Many Clipless Pedals | 8mm | Internal hex socket on the axle. |
| Some Road Pedals | 15mm | Less common now with clipless. |
Important Safety Tip
Always wear safety glasses when working on your bike, particularly when applying significant force such as when loosening pedals. This helps protect your eyes from flying debris.
Frequently Asked Questions
What size is the most common pedal wrench size?
The most common pedal wrench size is 15mm. Many pedals are designed to fit this size, making a 15mm pedal wrench a staple tool for most cyclists. Using the wrong size can damage your pedals.
Why is a pedal wrench thinner than a standard wrench?
Pedal wrenches are specifically designed to be thinner because the wrench flats on pedals are often very narrow. A thicker standard wrench might not fit properly between the pedal and the crank arm. Correct pedal wrench size ensures a secure fit.
Can I use a regular wrench instead of a pedal wrench?
While technically possible, it’s not recommended. Standard wrenches are often too thick and may not fit properly. Using a regular wrench can damage your pedals or the crank arms. Using the right pedal wrench size avoids damaging your bike.
Are all pedal wrench sizes the same for left and right pedals?
Generally, yes. Both the left and right pedals usually require the same pedal wrench size. The difference lies in the thread direction – one is right-hand threaded and the other left-hand threaded, not the tool size. Using the correct pedal wrench size is crucial regardless of thread direction.
So, there you have it! Figuring out the right pedal wrench size might seem like a small detail, but it can save you a whole lot of frustration (and potentially damaged pedals). Now you’re armed with the knowledge to confidently choose the perfect tool for the job. Happy riding!