When you’re working on your bike pedals, having the right tools makes all the difference. A pedal wrench is designed specifically to fit the narrow flats on pedal spindles, giving you the leverage you need without damaging your bike. But what size is a pedal wrench, and why does it matter?
Knowing the correct size helps you choose the perfect tool for easy installation or removal of pedals. Most pedal wrenches come in standard sizes that fit common pedal models, so understanding these sizes ensures you won’t struggle with slipping or stripped pedals. Whether you’re a casual rider or a seasoned mechanic, getting the right pedal wrench size saves time and effort on your bike maintenance.
Understanding What Size Is a Pedal Wrench
You use a pedal wrench sized specifically to fit the narrow flats on pedal spindles. Most pedal wrenches measure 15mm across the flats, matching the standard pedal spindle width. Some pedals might require a 9/16-inch wrench, which equals approximately 14.3mm, common in certain BMX or older bike models. You find pedal wrenches with long handles, usually 8 to 12 inches, to provide extra leverage during pedal installation or removal.
You select a pedal wrench based on the pedal type your bike uses. Professional mechanics often keep both 15mm and 9/16-inch wrenches to cover all pedal sizes effectively. You avoid using generic open-end wrenches or adjustable wrenches to prevent damaging the pedal flats. In cases where pedal hex keys are used, such as 6mm or 8mm hex sizes, a pedal wrench becomes unnecessary.
A pedal wrench’s sizing focus revolves around the width between the flats on the pedal spindle rather than its overall length or handle size. You recognize that a precise fit reduces slipping and stripping, making pedal maintenance smoother and safer.
Common Sizes of Pedal Wrenches
Pedal wrenches come in specific sizes that match the flats on pedal spindles. Knowing these sizes helps you select the right tool for your bike maintenance, ensuring a secure grip and efficient pedal removal or installation.
Standard Sizes Used in Bicycle Maintenance
Most pedal wrenches feature a 15mm opening, which fits the flats on the majority of modern pedal spindles. You might also encounter a 9/16-inch size common in BMX bikes and older models. Professional mechanics usually keep both sizes available to cover a wide range of pedal types. Using a properly sized pedal wrench prevents damage and provides the leverage required for tight pedals.
Differences Between Metric and SAE Sizes
Metric pedal wrenches mainly come in 15mm, while SAE wrenches often use 9/16 inches. Metric sizes suit most road and mountain bikes, since manufacturers standardize on millimeters. SAE sizes appear more in BMX and vintage bikes, where inch measurements were more common. Choosing the correct system ensures correct fitment—mixing metric and SAE tools risks slipping or damaging pedal flats.
How to Choose the Right Pedal Wrench Size
Choosing the correct pedal wrench size ensures a secure fit and prevents damage while working on your bike pedals. Matching your wrench size to your pedal specifications streamlines installation and removal.
Identifying Your Bike Pedal Specifications
Determine your pedal spindle size by checking your bike’s manual or inspecting the pedal flats. Most modern bikes use 15mm pedal spindles, while BMX and older models often have 9/16-inch spindles. Confirm whether your bike uses metric (millimeters) or SAE (inches) measurements to avoid using incompatible tools. Note the pedal type—some require hex keys instead of wrenches, so identifying your pedals prevents mismatched tool use.
Tools to Measure Pedal Wrench Size Accurately
Use a caliper to precisely measure the width across the flats of your pedal spindle. A ruler or tape measure can work but may not offer the accuracy necessary to avoid stripping pedals. If you don’t have access to measuring tools, take your pedal or bike to a bike shop for exact sizing. Maintain clear measurements in millimeters or inches to select the appropriate pedal wrench size—typically 15mm or 9/16 inch—to ensure a firm grip without slipping.
Tips for Using a Pedal Wrench Effectively
Apply consistent force when loosening or tightening pedals, using steady pressure rather than sudden jerks to avoid damaging the pedal flats. Position the wrench on the correct side of the bike to turn the pedals in the proper direction—left pedal loosens counterclockwise, right pedal loosens clockwise. Hold the bike steady or secure it in a repair stand to prevent unwanted movement during pedal removal or installation. Use a pedal wrench with a longer handle for increased leverage on stubborn pedals, but avoid excessive force that risks stripping threads. Keep the wrench clean and free of grease to maintain a solid grip on the flats. Verify the pedal spindle size matches the wrench opening before use to ensure a precise fit and reduce slipping. Check the condition of pedal threads regularly, applying grease or anti-seize compound before reinstallation to ease future removal and protect against corrosion.
Conclusion
Choosing the right pedal wrench size makes your bike maintenance faster and safer. Whether you’re working with a 15mm or 9/16-inch pedal spindle, having the correct tool ensures a secure grip and prevents damage to your pedals.
Keep your wrench clean and apply steady pressure for the best results. Knowing your pedal’s specifications and using the proper size wrench will save you time and frustration every time you need to install or remove pedals.
Frequently Asked Questions
What is a pedal wrench used for?
A pedal wrench is a specialized tool designed to fit the narrow flats on pedal spindles, providing proper leverage to install or remove bike pedals without damaging them.
What size pedal wrench do I need?
Most modern bikes require a 15mm pedal wrench, while BMX and older models typically need a 9/16-inch wrench. Checking your bike manual or measuring the pedal flats helps determine the correct size.
Can I use a regular adjustable wrench for pedals?
It’s not recommended to use a generic adjustable or open-end wrench, as they may slip and damage the pedal flats. A pedal wrench fits precisely and offers better leverage.
How do I know if I have the right pedal wrench size?
Verify the pedal spindle size by inspecting the pedal flats or referring to the bike manual. The wrench opening should snugly fit the spindle width (usually 15mm or 9/16 inch).
Should I grease pedal threads before installation?
Yes, applying grease or anti-seize to pedal threads before installation helps prevent corrosion and makes future removal easier.
Which direction do pedals loosen?
The left pedal loosens counterclockwise, while the right pedal loosens clockwise. Remembering this helps avoid damage during removal.
How can I avoid stripping pedals during maintenance?
Use the correct pedal wrench size, apply steady and consistent force, avoid excessive leverage, and keep the wrench clean for better grip and control.
Are pedal hex keys a good alternative to pedal wrenches?
Pedal hex keys can be used if your pedals have hexagonal fittings, making a pedal wrench unnecessary in those cases.
Why do professional mechanics keep multiple pedal wrench sizes?
Because bikes can have different pedal spindle sizes, having both 15mm and 9/16-inch wrenches ensures compatibility with most pedal types.
What’s the difference between metric and SAE pedal wrenches?
Metric pedal wrenches are typically 15mm, while SAE wrenches are 9/16 inch. Using the correct system prevents slipping and damage.
