Replacement bicycle crank arm designed for reliable, long-lasting performance across city, folding and mountain bikes. Confidence on commutes and loaded rides comes from forged construction and correct crank length. Is the Alps2Ocean Bike Crank Arm the right match for your crankset and spindle interface?
⚡ At a Glance
- • Build Quality: Forged Alloy 6061 construction for high strength and resistance to deformation
- • Best for: Cyclists replacing a left crank arm on city, folding, MTB and e-bikes
- • Not ideal for: Riders with a square-hole spindle or those who need a right-side crank arm
Forged Alloy 6061 left-side crank arm available in five lengths, designed for 9/16 inch pedals. Diamond hole spindle interface requires matching orientation and is supplied with crank bolt.
Dependable strength - thanks to Forged Alloy 6061
Forged Alloy 6061 undergoes shaping under high pressure, producing a dense, high-hardness aluminium alloy with good fatigue resistance. The forging process reduces weak points compared with cast alternatives.
High tensile strength resists bending under heavy pedalling loads, making it suitable for commuter, cargo and e-bike use. Durable finish means fewer replacements over the long term.
Correct pedalling feel - with multiple length options (152–175mm)
Five length choices correspond to common crank arm measurements so chainline and leverage remain consistent with original setups. Standard 9/16 inch pedal threading matches most adult pedals.
Select the matching length to preserve cadence and bike geometry, helping maintain comfortable pedalling and accurate shifting. Simple way to restore original ride dynamics after wear or damage.
Secure mounting - thanks to Diamond Hole spindle interface and included bolt
Diamond hole interface requires the crank orientation to match the spindle shape on both sides, and supplied crank bolts secure the left arm to the axle. Left arm is marked L for correct installation.
When paired with a compatible diamond-spindle crankset, the arm fits securely and maintains alignment. Correct left-side installation avoids function loss or safety issues.
✨ The 4 Key Reasons for Alps2Ocean Bike Crank Arm
- Forged Alloy 6061 - Handles heavy loads without deforming over long rides
- Five length options (152–175mm) - Match original crank length for correct pedalling cadence
- 9/16 inch pedal thread - Fits standard pedals used on most adult bicycles
- Includes left crank bolt - Saves time during repair with included mounting hardware
📋 Technical Details at a Glance
- Category: Bicycle crank arm
- Brand: Alps2Ocean
- Material: Forged Alloy 6061
- Length options: 152mm, 160mm, 165mm, 170mm, 175mm
- Pedal thread: 9/16 inch
❓ Frequently Asked Questions
Q: How do I know if this crank arm will fit my bike?
A: Check that the crankset uses a Diamond Hole spindle interface, that pedals use a 9/16 inch thread, and choose the arm length that matches your original crank (152–175mm).
Q: Is the crank arm left or right sided?
A: The item is a left crank arm only and is marked L for installation on the left side; installing the wrong side will prevent correct function.
Q: Are mounting bolts included?
A: Yes, the package includes crank bolts so no separate mounting hardware is required.
🏆 Our Verdict
Suitable for riders who need a durable left-side replacement across a wide range of bike types, from commuters to e-bikes. Forged Alloy 6061 construction combined with multiple length options and a Diamond Hole interface makes matching original fit and strength straightforward. Balances practical durability and compatibility for a long-lasting OEM-style repair.
