Bike Comparison
    MSRP
    ($290)$549
    Where to Buy
    $1

    At

    $549

    At Trek

    Category
    General YouthGeneral Youth
    Weight
    25.8 lbs21.1 lbs
    2.4
    AluminumAluminum
    Fork
    Aluminum
    Wheels
    Aluminum
    Wheel Size
    20″24″
    Brakes
    RimRim
    Groupset
    microSHIFT Acolyte
    Drivetrain
    1 × 8
    Brand Site

    decathlon.co.uk

    trekbikes.com

    Summary
    The B’TWIN Rockrider ST 900 Kids Alloy Mountain Bike - 20" is a 20″ aluminum frame general youth bike with rim brakes.
    Similar Bikes
    Accessories
    Gear Range

    A bike with lower gearing will be easier to ride up steep hills, while a higher top end means it will pedal faster down hills.

    Lowest gear

    (climbing)

    18 mph

    2024 Wahoo 24 Path

    Highest gear

    (descending)

    Spec Level

    Based on build material and quality level of the frame, fork, wheelset, groupset, suspension system, and more.

    Geometry
    Specs
    Frame

    Alpha Silver Aluminum, 24''

    Fork

    Take on new challenging terrain (roots, stones, gravel, etc.) with ease thanks to the travel of the front suspension fork.

    Wahoo 24'' alloy, V-brake bosses, ThruSkew 5mm QR

    Bottom Bracket

    Sealed cartridge, 68mm

    Headset

    Integrated, sealed cartridge bearings

    Stem

    Bontrager Comp, 31.8mm, Blendr compatible, 7 degree, 50mm length

    Handlebar

    Bontrager alloy, 31.8mm, 15mm rise, 580mm width

    Saddle

    Kids' padded, integrated seatpost, Blendr light mount, 31.6x270mm

    Pedals

    Kids' Satellite, 9/16 thread

    Grips

    Size: 24" wheel, Kids' grip, 108mm width, lock-on; Size: 24" wheel, Kids' grip, 110mm width; Size: 24" wheel, Kids' grip, 108mm width

    Groupset
    Rear Derailleur

    microSHIFT Acolyte M5180S, 34-38T max cog

    Crank

    The new aluminium chainset has a 140 mm crank that is designed for a child's leg length. This lightweight chainset allows you to start pedalling more easily. The double chain guard prevents the chain from derailing.

    Alloy, 28T steel ring, chainguard, 127mm length

    Shifters

    microSHIFT Acolyte SL-M6285, 8 speed

    Cassette

    microSHIFT Acolyte H083, 11-38, 8 speed

    Chain

    KMC Z8

    Brakes

    Rim

    Alloy linear-pull

    Brake Levers

    Kids' alloy brake lever, black

    Wheels
    Rims

    Alloy 24'', 28h

    Front Hub

    Formula alloy, 100mm ThruSkew

    Rear Hub

    Formula FM32 alloy, 135x5mm

    Tires

    The tyres are designed for mountain biking. The lateral lugs provide good grip on turns. The tyres use SkinWall technology. This process makes it possible to reduce their weight, provide greater flexibility, therefore increasing their performance, grip and comfort. The recommended tyre pressure is displayed on the tyre sidewall (between 2 and 3.5 bar). 20-inch 1.7"-2.2" wide inner tube with Schrader valve.

    Bontrager Connection Comp, wire bead, 30 tpi, 24x2.00''

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