SRAM RED AXS E1 2x Power Meter Crankset DUB

Integrated power meter and chainrings

The power meter electronics and strain measurement system are incorporated into the one-piece chainring assembly. This reduces the number of separate interfaces, saves weight and creates a highly rigid connection between the chainrings and crankarms.

Locating the measurement system at the spider allows the SRAM RED AXS E1 2x Power Meter Crankset to capture the combined output from both legs. The system also reports left-to-right power balance, providing a useful indication of pedalling symmetry during endurance riding, threshold intervals and injury rehabilitation.

The balance figure is calculated from the distribution of torque through the crank rather than being produced by two completely independent measurement units. It is valuable for monitoring trends but should not be treated as a medical assessment.

Quarq power measurement

SRAM’s power meter technology is based on the established Quarq platform. The claimed plus or minus 1.5 per cent accuracy is designed to remain stable as temperature changes during a ride, which is particularly relevant in Australia when an early-morning start develops into a much hotter training session.

Hollow carbon crankarms

A revised carbon lay-up reduces crankarm weight while retaining the stiffness required for sprinting and high-output climbing. SRAM claims a 29-gram reduction from the previous RED generation.

The hollow structure places carbon material where it contributes to stiffness and strength while removing unnecessary mass from less heavily loaded areas. This gives the crankset a direct feel under force without adding the weight associated with solid or heavily reinforced crankarms.

One-piece aluminium chainrings

The two chainrings are machined as one integrated aluminium structure. This creates a stiff connection between the large and small rings, allowing SRAM to control the position of the shift ramps, pickup points and teeth more precisely than on independently mounted chainrings.

The result is fast front shifting under realistic riding loads. The one-piece design also resists relative movement between the chainrings, which can help maintain shift quality as the crankset accumulates use.

The compromise is that the chainrings and power meter form one replacement assembly. Individual worn chainrings cannot be replaced separately.

X-Range gearing

Each available chainring combination uses a 13-tooth difference:

• 46/33T
• 48/35T
• 50/37T

This relatively small step reduces the cadence change when shifting between chainrings. SRAM combines these chainrings with wide-range 12-speed cassettes to produce a broad overall gear range with more gradual progression through the drivetrain.

DUB construction

The 28.99mm SRAM DUB spindle is designed to balance stiffness, bearing size, sealing and broad frame compatibility. The correct Road DUB bottom bracket must still be selected for the bicycle’s threaded, press-fit or T47 bottom-bracket shell.

DUB refers to the spindle and bottom-bracket system, not one universal bottom bracket that fits every frame.

ANT+ and Bluetooth connectivity

ANT+ enables pairing with most premium GPS cycling computers, while Bluetooth provides compatibility with supported smartphones, training applications and indoor riding equipment. The SRAM AXS app can also be used for firmware management and battery checks.