How to Remove a Bicycle Crank (Step-by-Step Guide)

You need to remove your cranks—maybe to replace a worn crankset, service your bottom bracket, or upgrade your drivetrain. But cranks are held on differently depending on the type, and using the wrong method can damage your cranks or bottom bracket.

Removing bicycle cranks requires specific tools and techniques. The process differs significantly between square taper, splined (Octalink, ISIS), and modern direct-mount (Hollowtech II, GXP) cranks.

In this guide, I’ll walk you through removing each type of crank safely, including the tools needed, step-by-step instructions, and common mistakes to avoid.

Types of Cranks: Quick Identification

Before removing, identify your crank type:

Square Taper (Older/Entry-Level)

• How to identify: Square hole in crank arm where it attaches to bottom bracket
• Common on: Older bikes, entry-level bikes, some BMX bikes
• Removal: Requires crank puller tool

Splined (Octalink, ISIS)

• How to identify: Splined (ridged) interface between crank and bottom bracket
• Common on: Mid-range bikes from 2000s
• Removal: Requires splined crank puller

Direct-Mount (Hollowtech II, GXP, etc.)

• How to identify: Large hollow spindle, bolt-on design
• Common on: Modern road and mountain bikes
• Removal: Usually just requires Allen wrench (no puller needed)

Tools Needed

For Square Taper and Splined Cranks:

• Crank puller (specific to your crank type)
• Allen wrenches (usually 8mm for crank bolts)
• Wrench (for square taper crank bolts, if not Allen)

For Direct-Mount Cranks:

• Allen wrenches (usually 8mm or 10mm)
• Optional: Crank removal tool (for some Shimano cranks)

Removing Square Taper Cranks

Square taper cranks require a crank puller tool to remove.

Step 1: Remove the Crank Bolt

1. Locate the crank bolt: Found in the center of the crank arm
2. Remove the bolt: Use an 8mm Allen wrench or wrench (depending on bolt type)
3. Remove any washers: Set aside for reinstallation

Note: Some square taper cranks have a dust cap that needs to be removed first. Use a flathead screwdriver to pry it off.

Step 2: Install the Crank Puller

1. Thread the puller: Screw the crank puller into the crank arm threads
2. Hand-tighten: Turn clockwise until snug (don’t overtighten)
3. Check alignment: Ensure puller is straight

Important: The crank puller threads into the crank arm, not the bottom bracket spindle.

Step 3: Remove the Crank

1. Turn the puller handle: Turn clockwise to push against the bottom bracket spindle
2. Apply steady pressure: The crank should pop off as you turn
3. Remove puller: Unscrew the puller once crank is removed

Troubleshooting: If crank won’t come off:

• Ensure puller is threaded correctly
• Apply penetrating oil if crank is stuck
• Don’t force it—check that you’re using the right puller

Step 4: Remove the Other Crank

Repeat the process for the other crank arm (usually the non-drive side comes off easier).

Removing Splined Cranks (Octalink, ISIS)

Splined cranks use a similar process but require a splined crank puller.

Step 1: Remove the Crank Bolt

1. Locate the bolt: Center of the crank arm
2. Remove: Use appropriate Allen wrench
3. Remove dust cap: If present, pry off with flathead screwdriver

Step 2: Install Splined Crank Puller

1. Thread puller: Screw into crank arm threads
2. Ensure splines align: The puller should fit the splined interface
3. Hand-tighten: Don’t overtighten

Step 3: Remove the Crank

1. Turn puller handle: Clockwise to push against spindle
2. Crank should pop off: May require significant force
3. Remove puller: Once crank is off

Note: Splined cranks can be very tight. Ensure you’re using the correct puller for your spline type (Octalink vs ISIS).

Removing Direct-Mount Cranks (Hollowtech II, GXP)

Modern direct-mount cranks are easier to remove—usually no puller needed.

Shimano Hollowtech II

1. Remove crank bolt: Use 8mm or 10mm Allen wrench (center bolt)
2. Remove preload cap: Small plastic cap (if present)
3. Pull crank off: Crank should slide off the spindle
4. Remove other side: Non-drive side may have a retaining clip

Note: Some Shimano cranks require a special removal tool if the crank is stuck.

SRAM GXP

1. Remove crank bolt: Use 8mm Allen wrench
2. Pull crank off: Should slide off easily
3. Remove other side: Non-drive side may need a puller if stuck

Other Direct-Mount Systems

Most modern systems follow similar steps:

1. Remove center bolt
2. Pull crank off spindle
3. May require light tapping if stuck

Common Issues and Solutions

Crank Won’t Come Off

Causes:

• Crank is seized on spindle
• Wrong puller tool
• Crank puller not threaded correctly

Solutions:

1. Apply penetrating oil: Let sit for 10-15 minutes
2. Check puller: Ensure correct tool for your crank type
3. Re-thread puller: Make sure it’s threaded correctly
4. Use more leverage: Longer handle or breaker bar (carefully)
5. Heat: Apply heat to crank arm (careful—don’t overheat)

Stripped Crank Bolt

Cause: Overtightening or corrosion

Solutions:

1. Use penetrating oil: Let soak
2. Try different tool: Different size or type
3. Extract if necessary: May need bolt extractor
4. Prevention: Always grease threads before installation

Crank Puller Won’t Thread

Causes:

• Wrong thread size
• Damaged threads
• Wrong puller type

Solutions:

1. Check thread size: Ensure puller matches crank threads
2. Clean threads: Remove dirt or corrosion
3. Use correct puller: Square taper vs splined vs direct-mount
4. Tap threads: May need to clean up damaged threads

Safety Precautions

1. Support the bike: Use a bike stand or secure the bike
2. Protect yourself: Crank removal can require significant force
3. Don’t force it: If something won’t budge, check your method
4. Clean threads: Clean and grease threads before reinstallation
5. Check for damage: Inspect crank and bottom bracket for wear

Reinstalling Cranks

When reinstalling:

1. Clean threads: Remove old grease and dirt
2. Apply grease: Grease crank threads and spindle
3. Install crank: Slide onto spindle (or thread for square taper)
4. Tighten bolt: Use proper torque (usually 35-50 Nm)
5. Check alignment: Ensure crank is properly seated

Important: Always use proper torque when reinstalling crank bolts. Overtightening can damage threads; undertightening can cause crank to come loose.

Removing Bicycle Cranks FAQs

Summary: Right Tool for the Right Crank

Removing bicycle cranks requires the correct tool for your crank type. Square taper and splined cranks need a crank puller, while modern direct-mount cranks are usually easier to remove.

Key Takeaways:

• Identify crank type before starting (square taper, splined, or direct-mount)
• Use correct tools (crank puller for older types, Allen wrench for modern)
• Remove crank bolt first before using puller
• Apply penetrating oil if crank is stuck
• Clean and grease threads before reinstallation
• Use proper torque when reinstalling

With the right tools and technique, removing cranks is straightforward. When in doubt, consult your bike’s manual or seek professional help to avoid damaging components.