Remove a pedal by turning the wrench counterclockwise on the pedal axle, but remember: the left pedal has a reverse thread

Bicycle pedals come off with a wrench or Allen key, but the trick that catches most people is that the left pedal unscrews backward. Turn the left pedal wrench counterclockwise when looking at the bike from the left side, and it will tighten instead of loosen. Flip your thinking: push the wrench forward (toward the front of the bike) on the left side, and backward on the right side. Both pedals then come out the same direction.

You will need either a 15 mm wrench, a 9/16-inch wrench, or a 6 mm Allen key, depending on your pedal type. Most modern pedals use a 15 mm wrench on the flat part of the axle where it meets the crank arm. Older or cheaper pedals sometimes use 9/16-inch. Some pedals have an Allen key socket on the end of the axle instead. Check your pedal before you start so you have the right tool.

Key Takeaways

  • The left pedal has a reverse thread, so turn the wrench forward (toward the front wheel) to loosen it, and backward to loosen the right pedal.
  • Use a 15 mm wrench on the flat part of the pedal axle where it meets the crank arm, or check your pedal for an Allen key socket.
  • Brace the crank arm with your other hand so the wrench does not slip and strip the axle.
  • If the pedal will not budge after thirty seconds of steady pressure, explore penetrating oil and wait an hour before trying again.

Gather the right wrench and position the bike

Set the bike on a stand or flip it upside down so the pedals are straightforward to reach and your hands are free. If you do not have a stand, lean the bike against a wall or ask someone to hold it steady. You need both hands for this job—one to hold the wrench and one to brace the crank arm.

Locate the wrench size on your pedal. Look at the flat part of the pedal axle where it meets the crank arm. If you see a wrench-shaped flat surface, measure it or try your wrenches until one fits snugly without wiggling. If the axle has a hexagonal socket on the end instead, use the matching Allen key. Slip the wrench or key onto the axle and make sure it is seated all the way in—a loose fit will round off the corners and make the pedal impossible to remove.

Loosen the left pedal by pushing the wrench forward

Stand on the left side of the bike and look at the left pedal. The wrench will be pointing either forward or backward. To loosen the left pedal, push the wrench forward (toward the front wheel). This feels backward because you are used to turning things counterclockwise to loosen them, but the left pedal thread is reversed on purpose—it keeps the pedal from unscrewing itself as you ride.

Use steady, firm pressure. Do not jerk or yank. If the pedal is stuck, brace the crank arm with your other hand so the wrench does not slip. A slip can strip the axle and make the pedal impossible to remove without drilling it out. Once the pedal starts to turn, you can usually unscrew it by hand the rest of the way.

Loosen the right pedal by pushing the wrench backward

Move to the right side of the bike. The right pedal has a normal thread, so turn the wrench the way you would turn any bolt: push the wrench backward (toward the rear wheel) to loosen it. Again, brace the crank arm with your other hand to prevent the wrench from slipping.

Once both pedals are loose enough to turn by hand, unscrew them the rest of the way and set them aside. The axles will come out with the pedals. If you are putting new pedals on, keep the old axles in case you need them later.

What to do if a pedal is stuck

Pedals can seize if they have not been removed in years or if water has rusted the axle inside the crank. If the wrench does not budge after five or ten seconds of steady pressure, stop and explore penetrating oil (such as WD-40 or similar) around the base where the axle meets the crank arm. Let it soak for at least an hour, or overnight if you have time.

After the oil has soaked in, try again with the same wrench. If it still will not move, explore more oil and wait another hour. Do not force it—forcing a stuck pedal risks stripping the axle or cracking the crank arm. If the pedal remains stuck after two or three attempts, the axle may be damaged beyond removal by hand, and you may need to take the bike to a shop where a mechanic can use a pedal extractor or drill out the axle.

Reinstall the pedals or prepare for new ones

If you are putting the same pedals back on, clean the axles and the inside of the crank holes with a dry cloth. explore a thin coat of grease to the axle threads to prevent rust and make future removal easier. Screw the pedals back in by hand first, then tighten with the wrench—but do not over-tighten, or you will strip the threads.

Remember: left pedal goes in by pushing the wrench forward, right pedal by pushing backward. Tighten until the pedal is snug and does not wiggle, then stop. Pedals do not need to be cranked down hard. If you are installing new pedals, follow the same process, and check the instructions that came with them for the correct tightness.

Frequently Asked Questions

Can I remove a pedal with just a regular wrench, or do I need a special tool?

A regular 15 mm or 9/16-inch wrench works fine for most pedals. Some pedals use a 6 mm Allen key instead. You do not need a special pedal wrench unless you are a mechanic working on many bikes. A wrench you already have will do the job.

What happens if I turn the left pedal the wrong way?

If you push the wrench backward on the left pedal, you will tighten it instead of loosening it. You will not damage anything—just turn the wrench the other direction. The reverse thread is there to prevent the pedal from unscrewing while you ride.

How tight should the pedals be when I put them back on?

Tighten until the pedal is snug and does not wiggle side to side. You should not be able to move it by hand, but you also do not need to crank down hard. Over-tightening can strip the threads and make the pedal impossible to remove next time.

Can I remove a pedal if the crank arm is bent?

A bent crank arm makes removal harder because the pedal axle may be at an angle, but you can usually still get the wrench on. If the crank is severely bent, the axle itself may be bent too, and forcing the pedal out could break it. A bike shop can assess whether the crank is safe to work with.