How to Get Pedals Off a Bike: Direction, Tools and Fixes

Every pedal on an adult bike is screwed into the end of a crank arm on a threaded spindle. Both sides come off in the same physical direction: turn the top of the pedal towards the back of the bike. That single rule works whether you're using a spanner or a hex key, and whichever side of the bike you're standing on.

What changes is the thread. The right-hand (drive-side) pedal uses an ordinary right-hand thread, so viewed from outside the bike it undoes anticlockwise. The left-hand pedal is reverse-threaded, so viewed from outside the bike it undoes clockwise. Get that pair the wrong way round and you'll be tightening a pedal that is already tight — and on an aluminium crank you can do real damage to the threads before you realise.

This is a two-tool job done on a garage floor, but the right two tools matter far more than brute strength. Most damage happens because someone used the wrong thing.

• A 15 mm pedal spanner. These are deliberately thin so they slide into the narrow gap between the pedal body and the crank arm. A standard combination spanner or an adjustable spanner is usually too wide to seat properly and will round the flats.
• A 6 mm or 8 mm hex key for pedals with a socket machined into the inboard end of the spindle. Many modern pedals offer both fittings.
• Penetrating oil if the pedals have been on the bike for years, particularly in an aluminium crank where corrosion grips the steel spindle.
• Grease or anti-seize for refitting, plus a rag.
• Ideally a work stand, though the bike on the ground with the brake applied works fine.

If you go in through the hex socket, you'll be standing on the opposite side of the bike and turning the key the other way round from the table above. The pedal still moves in the same direction as it always does. Trust the physical rule — top of the pedal towards the rear — rather than trying to remember which way the tool turns from wherever you happen to be standing.

A pedal that has sat untouched for a decade, especially in an aluminium crank, can feel welded in place. Work through this in order rather than reaching for more leverage:

• Re-check the direction. Nine times out of ten a pedal that "won't move" is being turned the wrong way. Stop before you damage anything.
• Add penetrating oil and wait. A drop at the joint between spindle and crank, left overnight, does more than any amount of force. Repeat it.
• Use the 15 mm flats rather than a small hex key if your pedal has both. A spanner gives more leverage and is far less likely to round the fitting.
• Warm the crank, not the pedal. A heat gun or hairdryer played on the crank eyelet around the thread can break the corrosion bond. Keep heat well away from carbon fibre, paint, hydraulic hoses and bearing seals, and never use a naked flame on a bike.
• Take it to a shop if the flats are already rounded, if the crank is carbon and seized, or if the spindle has started to chew the crank thread.

• Rounding the flats. Usually caused by an adjustable spanner that only grips two corners, or by a tool that isn't pushed fully home. If the flats are past saving, switch to the hex fitting.
• Turning the wrong part. Some pedals have an end cap or an adjuster on the outer face. That is for servicing the bearings, not for removing the pedal. The removal fitting is the flats or the socket at the crank end.
• Cross-threading on refit. Always start the thread by hand. It should turn in freely for the first few rotations; if it fights you immediately, you're cross-threaded. Back it out and start again.
• Swapping left and right. Pedals are handed and marked L and R. Forcing an L pedal into a right crank destroys the thread on both.
• Forgetting a spacer washer. Some pedals sit on a thin washer between the pedal and the crank. Keep it with its own side so the pedal goes back in the same position.
• Barking your knuckles. The moment the thread breaks free, your hand travels. Keep your knuckles clear of the chainring and the frame, and pull towards yourself rather than pushing across the bike.

A few designs break the pattern and are worth identifying before you start. Pedals with a hex fitting and no spanner flats can only be removed with the key, so make sure you have the right size rather than improvising. Quick-release pedals have a release collar or lever and don't need to be unscrewed at all. Pedals with an integrated power meter are usually fitted to a stated torque and can be damaged by a heavy-handed removal, so follow the maker's instructions exactly. And if the crank arm is carbon, treat any seized pedal as a job for a shop — carbon doesn't tolerate the clamping and heat that help with an aluminium crank.