The Fly Bikes Neutron 20 Inch Bike, a Ruben Alcantara signature model, boasts a sleek black design with thick tires and a sturdy CrMo frame. Its compact structure and front brake cable stand out beautifully against the white background.
The Fly Bikes Neutron 20 Inch Bike, showcasing a beige CrMo frame complemented by black handlebars, seat, and wheels, is displayed against a white background and comes equipped with the reliable Springhanger brake system.
Close-up of the wheel hub with spokes and bolts on the Fly Bikes Neutron 20 Inch Bike, featuring a small white logo.
A close-up of the Fly Bikes Neutron 20 Inch Bike's rear wheel hub features a logo, highlighting its dark spokes and chainset against a dark background. The CrMo frame enhances durability and strength, contributing to the bike's sleek design.
A close-up of a textured black bicycle pedal on a dark background, perfect for your next Fly Bikes Neutron 20 Inch Bike adventure.
Close-up of a brown seat, engraved with the Fly Bikes logo, mounted on the sleek CrMo frame of the Neutron 20 Inch BMX bike, set against a dark background.
Close-up of the handlebar grip on a Fly Bikes Neutron 20 Inch Bike, showcasing the textured surface and subtle pattern against a dark background.
Introducing the Fly Bikes Neutron 20 Inch Bike, a sleek black BMX with a CrMo frame, adorned with graphic designs and complemented by a brown seat, all strikingly contrasted against a dark background.
Diagram of the Fly Bikes Neutron 20 Inch bike featuring a CrMo frame with precise dimensions: 29", 20.75", 13.2", and 11.75". It includes handlebars standing at 9" and a fork width of 32mm, enhanced by angles of 100°, 20°, 71°, and 75° for optimal performance.

Description

The neutron is a subatomic particle, which has no electric charge, and a mass slightly greater than that of a proton... It's also an absolute banger of a bike!

The NEUTRON BMX Bike is designed to fit different riding styles, whether you're into tech street, transition, trails or all-around riding. This is an absolute beast of a bike that looks absolutely amazing. The effort Fly puts into their products is spot on. This is decked out with loads of Trebol and Fly parts creating a solid bike that absolutely rips!


This mid-range bike features a 100% CrMo main triangle frame and steering fork, sealed hubs, removable brake mounts with the Springhanger brake system, 3 piece CrMo crankset, and Ruben Alcantara signature Grips, Tires and Pedals.

Features
  • Chromoly main triangle and steering fork. The tubes that take the most abuse are 100% CrMo, so the Neutron holds up to hard riding without carrying dead weight.
  • 20.75" top tube, 13.2" chainstay. Middle ground geometry with a 75° head tube angle that suits tech street, transition, trails or just all round riding.
  • Sealed hubs front and rear. Trebol sealed bearing hubs with a 9T cassette driver keep grit out and keep spinning long after loose ball hubs give up.
  • Removable brake mounts, Springhanger brake. Run the Trebol Springhanger rear brake or strip the mounts off for a clean frame, whichever way you ride.
  • Ruben signature grips, tyres and pedals. 160mm Ruben 2 grips, 2.35" Ruben tyres and Ruben Graphite pedals, with the whole bike at 10.93 kg brakeless.

Specifications
  • Size: 20" wheels, 20.75" top tube
  • Frame: 4130 CrMo down tube, top tube and chainstays / 1020 Hi-Ten / removable brake mounts
  • Top tube: 20.75"
  • Chainstay: 13.2"
  • Head tube angle: 75°
  • Seat tube angle: 71°
  • Standover: 9"
  • Bottom bracket height: 11.75"
  • Fork: Integrated cone shape design / 4130 CrMo 1 piece steer tube / 1020 Hi-Ten legs / 32mm offset
  • Headset: Trebol internal sealed bearing
  • Stem: Trebol top load / forged 6061-T6 aluminium / 50mm
  • Bars: 1020 Hi-Ten / 9" rise / 29" wide / 10° backsweep / 2° upsweep
  • Grips: Fly Ruben 2 / 160mm long
  • Brakes: Trebol Springhanger / forged 6061-T6 aluminium
  • Brake lever: Generic / forged 6061-T6 aluminium
  • Cranks: Trebol 3 piece / 4130 CrMo / 170mm arm length
  • Bottom bracket: Mid / sealed bearing
  • Sprocket: Trebol / 6061-T6 aluminium CNC machined / 25T
  • Chain: 510 type / 74 links
  • Pedals: Fly Ruben Graphite / nylon and fibreglass compound
  • Front hub: Trebol / sealed bearing / 10mm male axle / 36H
  • Rear hub: Trebol / sealed bearing / 14mm male axle / 36H / 9T
  • Rims: Trebol / semi double walled / 6061-T6 aluminium / 36H
  • Tyres: Fly Ruben 2.35 front and rear / 60 TPI / 110 PSI
  • Seat: Fly Neutron Tripod / 100% synthetic leather / 7mm thickness
  • Seat post: Trebol Tripod / forged and CNC machined / 6061-T6 aluminium / 135mm
  • Weight: 10.93 kg / 24.10 lb (brakeless)
  • Note: Hub guards to suit: front, Fly Magneto hub guards. Rear non drive side, Colony Wasp cassette hub guard (nylon). Rear drive side, Colony freecoaster nylon drive side hub guard.

Assembly information

Your bike ships mostly assembled in the box. Finishing it takes most people 10 to 20 minutes with basic tools, and the video above walks through every step.

  • Fit the handlebars and line them up with the front wheel
  • Fit the front wheel, pedals and seat post
  • Check the brakes and tyre pressure before the first ride

Tools: Allen key set and a 15mm, 17mm or 19mm spanner for the pedals and axle nuts (bikes can vary between these three sizes). A socket is needed if installing pegs.

Rather have it done? Ask us about extra assembly before you order, or any local bike shop can finish the build for a small fee.

Fly Bikes Neutron 20 Inch Bike

Brand: Fly Bikes SKU:

$979.99 AUD

Or 4 payments of $244.99 AUD with

Colour - Flat Black

Top Tube Length - 20.75

Drive Side - Right Hand Drive

20 inch BMX sizing

A 20 inch bike is the standard adult BMX and suits riders from about 147cm up. At this wheel size the top tube is what changes the fit, so pick that by height.

Rider heightWheel sizeTop tube
60 to 91cm12"12 to 12.5"
81 to 106cm14"14 to 14.5"
96 to 122cm16"16 to 16.5"
122 to 147cm18"18 to 18.5"
147 to 157cm20"19.75 to 20.25"
157 to 168cm20"20 to 20.5"
168 to 175cm20"20.25 to 20.75"
175 to 183cm20"20.5 to 21"
183 to 190cm and up20"20.75 to 21.5"
160cm and up22"21 to 22.25"
160cm and up24"21.75 to 22"
160cm and up26"22 to 23"

Sizes overlap on purpose, so personal preference comes into it. If you land in two bands, riding style breaks the tie: longer for flow, trails and transitions, shorter for technical street and park.

How to measure

Stand your rider against a wall in the shoes they ride in, heels flat, and mark the top of their head. Measure from the floor to the mark.

Top tube is measured from the centre of the seat tube to the centre of the head tube, so it is not the same as the length of the tube you can see.

  • A 20 inch bike is the standard adult BMX and most riders end up there, so do not size a tall child down to a smaller wheel.
  • 22, 24 and 26 inch bikes are adult bikes with a bigger wheel, not bigger frames for taller riders.
  • Size up for stability through trails and transitions. Size down if you want the bike quick and twitchy for spins and grinds.
  • Top tube is fixed, but stem length, fork offset and bar position all shift how roomy the bike feels once you are on it.

Not sure? Send us their height and we will tell you what we would put them on.

Read the full buying guide

20 inch BMX sizing

A 20 inch bike is the standard adult BMX and suits riders from about 147cm up. At this wheel size the top tube is what changes the fit, so pick that by height.

Rider heightWheel sizeTop tube
60 to 91cm12"12 to 12.5"
81 to 106cm14"14 to 14.5"
96 to 122cm16"16 to 16.5"
122 to 147cm18"18 to 18.5"
147 to 157cm20"19.75 to 20.25"
157 to 168cm20"20 to 20.5"
168 to 175cm20"20.25 to 20.75"
175 to 183cm20"20.5 to 21"
183 to 190cm and up20"20.75 to 21.5"
160cm and up22"21 to 22.25"
160cm and up24"21.75 to 22"
160cm and up26"22 to 23"

Sizes overlap on purpose, so personal preference comes into it. If you land in two bands, riding style breaks the tie: longer for flow, trails and transitions, shorter for technical street and park.

How to measure

Stand your rider against a wall in the shoes they ride in, heels flat, and mark the top of their head. Measure from the floor to the mark.

Top tube is measured from the centre of the seat tube to the centre of the head tube, so it is not the same as the length of the tube you can see.

  • A 20 inch bike is the standard adult BMX and most riders end up there, so do not size a tall child down to a smaller wheel.
  • 22, 24 and 26 inch bikes are adult bikes with a bigger wheel, not bigger frames for taller riders.
  • Size up for stability through trails and transitions. Size down if you want the bike quick and twitchy for spins and grinds.
  • Top tube is fixed, but stem length, fork offset and bar position all shift how roomy the bike feels once you are on it.

Not sure? Send us their height and we will tell you what we would put them on.

Read the full buying guide
$979.99 AUD

Price match request

Fly Bikes Neutron 20 Inch Bike - Flat Black / 20.75 / Right Hand Drive

Metro bike shipping from $59.99

Regional and remote rates may differ

Free in-store pickup - Brisbane

Availability

Right Hand DriveLeft Hand Drive
Flat Black
Flat Grey

● In stock at LUXBMX ● With supplier ● Preorder ○ Sold out

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