Stable ride.

The RockShox SID World Cup Solo Air 100 Boost (51mm offset) Fork - 29/27.5 Plus brings together a stiff axle, snappy handling, and race-worthy speed that will satisfy even the most gram-conscious XC racers who won't compromise strength or durability in their quest for lightweight functionality. This model adds a hint of rake to decrease the bike's trail and make low-speed finesse sections more manageable. The result is less "dead" space between hub and the steering axis, which offsets the floppy, low-speed steering issues that arise from the longer trails produced by today's slacker geometries and taller wheels. Handling stays 26er-sharp at all speeds, whether climbing, shredding, or cleaning switchbacks and tricky terrain.

The SID's Solo Air spring features an easy-to-tune design with a single Schrader valve that controls air adjustment for both chambers. The feel of the spring is also customizable with RockShox's Bottomless Tokens, which alter the chamber's effective volume and compression curve to meet individual ramp-up preferences. While the Solo Air spring lets you adjust the fork for more trail-oriented terrain, the Power Bulges on the lower bushings ensure the SID is always ready to do what an XC bike is meant to do: attack and open up a gap on the climbs. Power Bulge's reinforcement also extends to terrain, helping the fork track truer across root lattices and fast descents so you can maintain the advantage you earned going up.

The fork's damper leg features the Motion Control DNA damping system, which fights off gravity with external rebound to reduce jarring and provide a controlled, smooth platform for navigation and attacking. The integrated Dual Flow technology boasts separate circuits for low- and high-speed compression as well as beginning- and end-stroke rebound damping for high-riding sensitivity over consecutive bumps and larger impacts. Pairing all this with a Rapid Recovery valve that rebounds quickly after full impacts means that the fork is always already prepped for the next hit.

  • A race-ready cross-country fork
  • 51mm rake decreases trail for snappier handling
  • Carbon fiber steerer tube and reinforced lower legs for stiff control
  • Charger Damper lets you dial in the lockout levels
  • Dual position air spring boasts adjustability with Bottomless Tokens
  • Compatible with OneLoc remote
  • Compatible with 29-inch and 27.5+ wheels
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