The SRAM Force AXS Power Meter Spider and the SRAM RED/Force AXS 107 BCD Power Meter Spider are two of our best-selling road power meters. They measure dual-leg power, are accurate, reliable and reasonably priced. However, we find that customers are often trying to figure out which option would be best for them. Below, you can see the similarities as well as the differences…with the main one being chainring configuration.
Compatibility: Both power meters are compatible with the latest generation of SRAM RED, Force D2, Force D1 and Quarq DZero 8-bolt cranksets.
Power Measurement: Both power meters are spider-based. That means, they measure power at the crank spider and are therefore able to measure power from both legs.
Left/Right Power Balance: Both power meters can provide left vs. right leg power balance data.
Batteries: Both power meters use CR2032 coin-cell batteries and get around 200 hours of battery life.
Communication Protocol: Both are ANT+ and Bluetooth compatible, which is standard for pretty much every power meter.
Calibration: Both have auto-zero functionally, which eliminates the need for manual zero-offsets.
Warranty: Both units come with a 2-year warranty.
Chainrings: So this is the big difference. The SRAM Force AXS Power Meter Spider (let’s call it version A for simplicity here), which is the newer of the two, features a 1-piece integrated power meter and chainring design. This makes the power meter lightweight and stiff. However, since the rings and power meter are one solid piece, when the chainrings wear out, you must replace the entire power meter. This compares to the SRAM RED/Force AXS 107 BCD Power Meter Spider (version B) that uses removable chainrings that can easily be replaced when worn. Please note however, the chainrings on the new integrated version A are made to last 50% longer than standard chainrings.
In addition to the ability to change chainrings, version B can be run in a 1x or 2x configuration. The new version A only comes as a 2x power meter.
Price: The Force AXS version A power meter is priced at $600. This compares to the SRAM RED/Force AXS 107 version B power meter which is priced at $590 with 1x chainrings or $677 with 2x chainrings.