RockShox SID Ultimate Flight Attendant Race Day 29" Suspension Fork D1

The RockShox SID Ultimate Flight Attendant Race Day 29" Suspension Fork D1 is RockShox's top-tier XC fork, built around the new Charger Race Day 2 Flight Attendant electronic damper. The three-position compression system — Open, Pedal, and Lock — adjusts automatically using a sensor suite that reads rider inputs and terrain in real time. No buttons to push mid-ride. The new Adaptive Ride Dynamics algorithm takes this further, learning rider preferences over time to make increasingly personalized decisions about suspension position. For hardtail builds, a fork-only mode is available; Auto Mode is also customizable to disable the Pedal or Lock position if preferred.

The chassis is built around 35mm tapered aluminum upper tubes — RockShox's chosen balance of stiffness and weight for modern XC geometry — with a machined crown to shave grams without sacrificing structure. DebonAir+ spring provides improved small-bump sensitivity at the top of travel with tunable mid-stroke support via volume tokens. The system runs cable-free on the shared SRAM AXS battery ecosystem and is rated IPX7 waterproof. Maxima Plush Dynamic Suspension Lube comes pre-installed to reduce friction and extend service intervals.

Specs at a Glance

• Wheel size: 29"
• Travel: 120mm
• Damper: Charger Race Day 2 Flight Attendant (3-position: Open/Pedal/Lock, auto-controlled)
• Spring: DebonAir+
• Chassis: 35mm tapered aluminum upper tubes, machined crown
• Steerer: 1.5" tapered
• Axle: 15x110mm BOOST
• Fork offset: 44mm
• Weight: 1,624g (120mm, with Maxle Stealth, no battery)
• Max tire width: 66mm
• Max rotor: 220mm
• Volume tokens: 0/3 or 1/3
• Waterproof rating: IPX7
• Color at RA Cycles: Electric Red