Description

The Fiend Type O 18" is built for young riders ready to progress their BMX riding. Pro-inspired geometry, a part chromoly frame, heat-treated chromoly cranks and a semi-sealed cassette hub give it the durability and performance for park, street, dirt and cruising.

Quality parts like the Fiend Crown Top Load stem, Fiend Team flangeless grips and wide 2.40" tyres provide plenty of control and comfort, while the light 11.3 kg build keeps the bike easy to handle. The Type O 18" is made for the intermediate level rider on the come up.

Features

18" top tube, modern geometry. Pro-inspired BMX geometry in a smaller package, so a young rider can progress on park, street, dirt and cruising.
Chromoly where it counts. A chromoly downtube adds strength to the Hi-Ten frame, and the 152mm cranks are heat-treated chromoly.
Semi-sealed cassette rear hub. A 9T right hand drive cassette on a 14mm axle, with a sealed Mid bottom bracket keeping the drivetrain smooth.
Wide 2.40" tyres. Front and rear 2.40" tyres give a young rider grip and a bit of cushion on rough ground.
Light 11.3 kg build. With the brake fitted it is easy to handle, which matters when a smaller rider is learning to throw the bike around.

Specifications

Size: 18" wheels, 18" top tube
Frame: Fiend Type O 18", Hi-Ten steel with chromoly downtube
Top tube: 18"
Chainstay: 12.25"
Head tube angle: 75°
Seat tube angle: 71°
Bottom bracket height: 11.625"
Fork: Fiend Type O, 100% Hi-Ten steel, tapered legs, 26mm offset
Headset: Sealed integrated
Stem: Fiend Crown Top Load, 50mm
Bars: Embryo Type O, Hi-Ten steel, 8.25" rise
Grips: Fiend Team flangeless
Brakes: Alloy 990 type
Brake lever: TRSH alloy, 2 finger type
Cranks: 152mm heat-treated chromoly
Bottom bracket: Sealed Mid, 19mm
Sprocket: TRSH steel, 25t
Chain: PYC 410
Pedals: Nylon with chromoly spindles
Front hub: TRSH, 36h, alloy, unsealed, 3/8" axle
Rear hub: TRSH, 36h, alloy, semi-sealed cassette, 14mm axle
Rear cog: 9t driver, right hand drive
Rims: 7X alloy single wall, front and rear
Tyres: 2.40", front and rear
Weight: 11.3 kg (with brake)

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.

Fiend Type O 18 Inch Bike (2026)

Name: Fiend Type O 18 Inch Bike (2026)
Brand: Fiend
SKU: KABX3393
Price: 549.99 AUD
Availability: OutOfStock

Brand: Fiend SKU: Click to copy the SKU and show the pick location

$549.99 AUD

Or 4 payments of $137.49 AUD with

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Top Tube Length - 18

An 18 inch bike suits a rider of about 122 to 147cm, usually 7 to 11 years old, on an 18 to 18.5 inch top tube. It is the last step before a full size 20 inch.

Rider height	Wheel size	Top tube
60 to 91cm	12"	12 to 12.5"
81 to 106cm	14"	14 to 14.5"
96 to 122cm	16"	16 to 16.5"
122 to 147cm	18"	18 to 18.5"
147 to 157cm	20"	19.75 to 20.25"
157 to 168cm	20"	20 to 20.5"
168 to 175cm	20"	20.25 to 20.75"
175 to 183cm	20"	20.5 to 21"
183 to 190cm and up	20"	20.75 to 21.5"
160cm and up	22"	21 to 22.25"
160cm and up	24"	21.75 to 22"
160cm and up	26"	22 to 23"

Sizes overlap on purpose, so personal preference comes into it. If your rider is near 147cm and still growing, look at a 20 inch instead: it is the size they will keep riding.

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.

Between an 18 and a 20? Take the 20. It is the size they will keep riding, and an 18 gets outgrown quickly.
They should be able to stand over the top tube with both feet flat on the ground.

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

Read the full buying guide