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  • RockShox - SID Ultimate 29in Boost Fork - Gloss Blue
  • RockShox - SID Ultimate 29in Boost Fork - Gloss Black
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Current Color

  • RockShox - SID Ultimate 29in Boost Fork - Gloss Blue
  • RockShox - SID Ultimate 29in Boost Fork - Gloss Black

RockShox SID Ultimate 29in Boost Fork


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    • Gloss Blue, 100mm, 42mm offset
    • Gloss Black, 100mm, 51mm offset
    • Gloss Black, 100mm, 42mm offset

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    SID Ultimate 29in Boost Fork

    For some riders, racing is a twice- a-year hobby, but for others, it's their life's true calling. RockShox builds the SID Ultimate 29in Boost Fork for the latter of the two, packing in the feel that elite cross-country racers crave, like gram savings, lively and supple suspension from the DebonAir spring, and Charger 2 RC2 damper, ramped up even further with new fluid and grease to keep things moving smoothly, whether you're hamming out short track sprints, or pushing to see how far you can go in the 24-hours in Old Pueblo. And in case you were getting jealous of the new colorways spotted in the Lyrik and Pike, RockShox ups the style points in the new SID Ultimate, with a signature Blue color that looks bold and fast when you're mashing down flowy ribbons of desert singletrack.

    The SID Ultimate comes in as just about top-tier in RockShox cross country lineup (second only to the SID Ultimate Carbon), and the updates start with the newly engineered Maxima Plush oil that reduces friction and improves smoothness in the stroke over previously used oils. This translates to improved lubrication on the seals that are all new themselves, moving to a lower-friction design that's inspired the the Motocross industry. This new oil partners up with a new type of grease in the air chamber that's designed for longer lifetime, and better wear than the grease tossed in in years past.

    The SID continues to use the Charge 2 damper we saw last year. While the other forks in RockShox's lineup see a change to the new Charger 2.1, RockShox engineers determined that the traditional Charger 2 performs better than the new damper in cross-country applications. This means a firmer climb, and lockout setting, for powering up punchy steep sections without losing a watt of power you're putting down. It still uses the highly-tunable DebonAir spring for consistent feel throughout the travel, and compression adjust.

    • RockShox's SID soars to the front of the XC scene
    • New Maxima Plush oil reduces friction, silences damper noise
    • All-new seals improve smoothness, aim to eliminate friction
    • Air chamber uses new grease that's just as smooth, lasts longer
    • Charger 2 damper excells in cross-country applications
    • Highly-tunable DebonAir spring for consistent feel through travel
    • Available in the new SID Blue for a flashy upgrade to your ride
    • 100-and-120mm options with 51-or-42mm offset to compliment your bike's geometry
    • Item #RSX009Q

    Tech Specs

    100mm, 120mm
    Stanchion Material
    Fast Black-coated aluminum
    Lower Material
    Crown Material
    forged, hollow 7050 aluminum
    Wheel Size
    Steer Tube Diameter
    1-1/8 - 1-1/2in tapered
    Stanchion Diameter
    42mm, 51mm
    Spring Type
    Charger 2 RC2
    high-speed compression, low-speed compression, rebound
    15 x 110mm Boost
    Brake Compatibility
    post-mount disc
    Recommended Use
    Manufacturer Warranty
    2 years

    Tech Specs

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