Upgrading the cockpit on an existing AXS bike usually means buying levers and calipers separately, then sourcing a head unit on top of that. The SRAM Red AXS E1 Upgrade Kit bundles all three into a single box: a left and right Red E1 HRD shift-brake lever pair, flat-mount 2-piston hydraulic disc brake calipers with 20mm offset, and a Hammerhead Karoo GPS bike computer. No derailleurs, no charger, no crankset. This is a cockpit and braking upgrade designed to drop onto a bike that already has AXS derailleurs installed.

The E1 generation levers represent a full redesign from previous Red AXS versions. The hood shape fits a broader range of hand sizes, and the carbon brake lever uses a revised pivot location that puts one-finger braking power within reach from both the hoods and the drops. Reach Adjust lets you reposition the lever closer or farther from the bar, while Contact Point Adjustment changes where the brake engages in the lever stroke. Both adjustments are independent, so dialing in your setup does not compromise the other setting. Each lever also has a Bonus Button on the inside of the hood that can scroll through Karoo data screens or serve as an auxiliary shift input through the AXS app.

The flat-mount calipers ship pre-bled with the hose and fluid already connected, which typically means installation does not require a full brake bleed. The system is compatible with all generations of AXS derailleurs, so whether you're running D1, D2, or E1 derailleurs, the levers pair directly. The included Hammerhead Karoo integrates with the AXS ecosystem for component monitoring, firmware updates, and ride data in one place.