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Please note that, in order to reduce production and delivery times, bike specifications are subject to change by the manufacturer without notice. Please be aware that these changes might not be reflected on product pages and images.
The Mongoose Legion L100 BMX bike is a rad BMX bike for riders of any age or ability that are after a totally dialled freestyle machine. The L100 is an extremely capable BMX bike which is ideally suited to all riders who want to step up their game. The tough chromoly frame and fork is built with modern BMX geometry for the ultimate riding experience. The L100 is equipped with 2 piece tubular chromoly hollow spindle cranks which are reliable for the best ride every single time. While the aluminium U-Brake gives you the control that you need in the skate park or streets. You'll be rolling on 20x2.4" tyres and tough Xposure Infinity-XD aluminium double wall 36H rims for a smooth ride. The Mongoose Legion L100 BMX bike offers some awesome spec which creates a versatile freestyle machine which is ready for easy curb jumps or advanced aerial assaults at the skate park.
Features
- Mongoose full 4130 Chromoly frame, tapered headtube, removable brake mounts, and mid BB shell.
- 175mm 2-piece tubular chromoly hollow spindle cranks with a 25T alloy chainring and mid sealed bearing bottom bracket.
- 20” x 2.4” tires mounted on wide aluminium double wall 36H rims with 3/8” female axle front hub and 9T cog sealed bearing cassette rear hub.
- 4130 chromoly handlebar and fork, 50mm stem, threadless sealed integrated headset, and Alloy U-brake.
- 21-inch top tube length. Suggested rider height is 5'8" and up.
SKU | MGM41201U20OS |
---|---|
UPC | 038675218628 |
Season | 2021 |
Click & Collect | Yes |
Frame | CrMo 4130 |
Frame Material | Steel |
Fork | CrMo 4130 |
Fork Material | Steel |
Crankset | CrMo Tubular 2-piece, hollow spindle 25T aluminium chainring |
Pedals | Mongoose, nylon |
Chain | KMC S1 |
Brake Type | Rim Brake |
Brakes | Alloy U-Brake |
Brake Levers | Alloy |
Cassette | Single-speed, 9T cassette driver |
Wheel Size | 20" |
Tyres | 20 x 2.4", wire bead |
Rims | Xposure Infinity-XD, aluminum double wall, 30 mm ID, 36H |
Hubs | Aluminum, Ball Bearing, 3/8" Axle, 36H |
Spokes | 14G, steel, black |
Bottom Bracket | Mid sealed bearing, 8-spline spindle |
Handlebar | Mongoose, CrMo 4130, 29" width, 8.75" rise |
Headset | External, 1-1/8" Threadless |
Grips | Mongoose MushXL, 160 mm |
Stem | Mongoose, Threadless Top Load, 50 mm |
Saddle | Mongoose Pivotal |
Seatpost | Pivotal, steel, 250 mm, 25.4 mm |
Sizing | 20 Inch |
20" Freestyle BMX Sizing Chart
Top Tube
Top Tube
Top Tube
Top Tube

Legend
ST Seat Tube
TT Top Tube
CS Chain Stay Length
HTA Head Tube Angle
STA Seat Tube Angle
BD Bottom Bracket Drop
HT Head Tube
FL Fork Length
R Reach
S Stack
WB Wheel Base
Size |
20inch | Wheel Size | 20" | Frame Size | 20inch | ST Seat Tube (mm) | 223.0 | TT Top Tube (mm) | 534.0 | CS Chain Stay Length (mm) | 348.0 | HTA Head Tube Angle (°) | 75.0 | STA Seat Tube Angle (°) | 71.0 | HT Head Tube (mm) | 120.0 | S Stack (mm) | - | WB Wheel Base (mm) | 925.0 |