SRAM's Lightest, Stiffest Crank - Now Optimised for Short-Arm Cyclocross Use

The SRAM RED Crank Arm Assembly is the top-tier crank arm in SRAM's road groupset range - the lightest and stiffest crank SRAM makes, built from hollow carbon arms with an optimised layup that reduces weight further than previous RED crank generations without compromising the structural integrity that a top-tier competition crank demands.

This specific listing is for the cyclocross arm length versions - 150mm and 155mm. These shorter arm lengths are specifically offered for cyclocross racing where the shorter crank provides more ground clearance during cornering and dismount/remount sequences, reducing the risk of pedal strike and improving handling on the technical sections of a CX course. The inclusion of these shorter lengths reflects SRAM's commitment to providing more crank arm length options than previous generations to ensure the crank works for the widest range of riders and disciplines.

This listing is for crank arms only - chainrings are sold separately and must be compatible with the 8-bolt Direct Mount SRAM interface. No bottom bracket is included - the DUB spindle interface requires a compatible DUB bottom bracket suited to your frame's BB shell standard. Confirm your frame's BB shell before purchase. Pedal axles are not included - standard 9/16-inch pedals are used.

Hollow Carbon Arms, DUB Spindle, and 8-Bolt Direct Mount

The hollow carbon arms are the defining construction feature of the RED crank - SRAM's manufacturing process that creates a hollow internal structure within each carbon arm, removing unused material from the arm's interior while maintaining the outer skin where structural loads are carried. The optimised layup on this generation refines the carbon fibre orientation within the arm wall to reduce weight while maintaining or improving stiffness compared to the previous RED crank arm construction.

The DUB (Durable Uniform Boost) spindle interface uses a 28.99mm diameter spindle - SRAM's proprietary standard that provides durability and simplified maintenance compared to earlier spindle standards. DUB bottom brackets are available in threaded, press-fit, and other shell formats to suit different frame specifications.

The 8-bolt Direct Mount chainring interface accepts SRAM's direct mount chainrings directly without a separate spider - reducing weight and improving the stiffness of the chainring-to-crank interface compared to a bolt-circle-diameter spider mount. The 8-bolt SRAM Direct Mount interface is specific to SRAM's direct mount chainring range - confirm chainring compatibility before purchase.

Chainline, Compatibility, and Cyclocross Application

The 43mm chainline and compatibility with 135/142mm road disc hubs over 415mm chainstays covers the standard geometry for modern disc brake cyclocross and gravel bikes. For cyclocross racing specifically, the 150mm and 155mm arm lengths paired with the RED crank's stiffness and minimal weight provide a competition-ready crank specification without the compromise of arm lengths that would reduce clearance or handling performance on a CX course.

FAQs

Are chainrings included with the RED Crank Arm Assembly?

No. Chainrings are sold separately. The crank uses an 8-bolt Direct Mount SRAM interface - confirm your chainring is compatible with this interface before purchase.

Is a bottom bracket included?

No. The DUB spindle interface requires a compatible DUB bottom bracket for your frame's BB shell standard - threaded, press-fit, or other formats. Confirm your frame's BB shell before purchasing a bottom bracket separately.

Why are 150mm and 155mm arm lengths offered for this listing?

These shorter arm lengths are specifically suited for cyclocross racing where reduced crank arm length improves ground clearance during cornering and dismount/remount sequences, reducing pedal strike risk on technical CX course features.

What is the DUB spindle interface?

DUB (Durable Uniform Boost) is SRAM's 28.99mm diameter spindle standard, offering durability and simplified maintenance. It is compatible with DUB-specific bottom brackets available in multiple shell formats.

What makes the RED crank arm the lightest SRAM offers?

The hollow carbon arm construction uses an optimised carbon fibre layup that removes unused interior material while maintaining the structural integrity of the arm's outer skin where loads are carried - producing the lowest possible weight while maintaining the stiffness needed for a top-tier competition crank.

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