$389.99
THUMPER
    $389.99 (USD$)

    THUMPER

    APPETITE FOR DIRT
    For real mountain bike performance, the Thumper is bang on! The aluminum frame and quality components will satisfy every kid’s taste for dirt. With 50 mm of travel — more than most! — the Spinner fork offer real damping performance. Plus, a stable geometry ensures the Thumper is easy and safe to ride. Even the crank and saddle are sized specifically for a 20” bike, so you know the fit is as good as the ride.

    • 50 mm Spinner fork has more travel and better damping for real trail performance
    • Double-wall alloy rims and Kenda Smallblock 8 tires are light, tough and durable
    • Youth-sized components deliver on fit and safety
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    Colors

    Technologies

    Specifications

    Frame Opus 6061 Aluminum
    Fork Spinner Grind 50 mm
    Weight (lb) 23.4
    Sizes 20"
    Color(s) Mirror Green
    Shifters SRAM 3.0 Twist 7
    Front Derailleur N/A
    Rear Derailleur SRAM X3
    Brakes Tektro V-Brake
    Brake Levers Tektro Alloy
    Crank Samox Alloy 127 mm
    Chainrings 36
    Bottom Bracket 5 pc Steel
    Cassette Shimano Tourney 14-34
    Chain KMC Z51
    Headset VP Semi-Integrated Sealed
    Handlebar Opus Junior 25.4
    Stem Promax 60 mm 15°
    Grips/Tape Opus Kraton
    Saddle Opus Junior
    Seatpost Opus Junior 27.2 x 300
    Wheels/Rims Ace Double wall
    Hubs Joytech
    Tires Kenda Smallblock Eight 20 x 1.75
    Pedals Wellgo Resin

    Geometry

    Geometry diagram
      20"
    Riders's height  
    ± cm
    ± 0"
    Size (cm)
    S - Seat tube (effective center-center in mm) 305
    TT - top tube (effective center-center in mm) 455
    HT - Head tube (mm) 100
    HA - Head angle (mm) 71
    SA - Seat angle (mm) 74
    CS - Chain stay (mm) 390
    D - BB drop (mm) 8
    ST - Stack (mm) 420
    RE - Reach (mm) 334
    SO - Stand over (mm) 524
    Handlebar width (mm) 540
    Stem length (mm) 60
    Crank length (mm) 127
    Geometry diagram
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