20" Legion L10

Smoother shifting, more powerful brakes, better suspension fork performance. The Avalanche Expert is equipped with the most capable components within the lineup, feeding you the confidence to progress your singletrack skills on climbs, descents and all the straightaways you can handle.


Currently taking pre-orders for late summer through winter delivery. Call the store for the latest information on models, sizes, dates and availability. Due to Covid-related stresses on the supply chain, all bike brands are experiencing delays of up to 12 months for popular models. Those with pre-orders in place will get priority allocations when limited stock arrives. 03 9557 6461


With the Legion Series, Mongoose offers a full line of freestyle BMX bikes for riders of all ages and ability levels. The Legion L10 is a great first 20” BMX bike that features the geometry and feel preferred by today’s riders!



-Mongoose hi-tensile steel frame and loose ball BB.

-Drivetrain features a 25T steel chainring and 9T cassette driver.

-20” x 2.25” tyres mounted on wide aluminium double wall 36H rims with 3/8” front and rear axles.

-Hi-Tensile steel handlebar and fork. 8-inch bar height and 27.5-inch wide.

-20” top tube length. Suggested rider height is 5’3” and up.

The Urban Pedaler Promise
Each bike purchased with us includes:


  • Professionally built and inspected by an experienced bicycle technician
  • Free minor adjustments for 30 days from purchase
  • Free first tuneup between 3 and 6 months from purchase – valued at $149 – does not include parts
  • Lifetime Warranty on bike frames and Limited Warranty on complete bikes, subject to brand-specific inclusions

Frame Hi-Ten steel, BMX freestyle geometry

Fork Hi-Ten steel



Crank 3-piece, tubular chromoly, 25T steel chainring

Chain KMC S1

Bottom Bracket American loose ball

Cassette Single-speed, 9T cassette driver



Rims Aluminium single wall, 24 mm ID, 36H

Front Hub Aluminium, ball bearing, 3/8 in axle, 36H.

Rear Hub Aluminium, sealed-bearing cassette, 14mm axle, 36H

Spokes 14G, stainless steel, Black

Tires 20" x 2.30", Wire bead


BRAKES U-brake, Aluminium



Handlebar Hi-Ten steel, 27.5” width, 8” rise

Pedals Mongoose, nylon

Stem Mongoose, threadless top load, 48mm

Headset Threadless, integrated 1-1/8", cartridge bearing

Seat Post Pivotal, Steel, 250mm, 25.4mm

Saddle Mongoose, steel rails

Grips Mongoose Mush, 145mm

Limited availability, call for up to date info

These will begin arriving in some sizes asap and are expecting to be filled out through the season. Call store for the latest information on dates and availability. Due to factory shortages, most bike brands are experiencing delays. Those with pre-orders in place will get priority allocations when limited stock arrives. 03 9557 6461