Inspection
Frame condition
Inspect the frame, fork, welds, and high-stress areas for cracks, dents, or prior repairs.
GT
2021 GT Mach One Junior
Previous used estimate
$159 - $164
Actual value depends on condition, size, and local demand.
Value Guide market data · 2021 GT Mach One Junior
12-month projected trend
11%
Direction and magnitude, not judgment
vs. category average
2%
Drops faster than category avg
Price over time - 2021 GT Mach One Junior
Values based on actual sales data. Enter your bike's specifics to get a precise valuation.
All Mach One model years
2021$159 - $164Currently viewing
2020$138 - $142▼ 13% vs. 2021
2019$124 - $128▼ 22% vs. 2021
2018$122 - $126▼ 23% vs. 2021
2017$109 - $112▼ 32% vs. 2021
2016$102 - $105▼ 36% vs. 2021
2015$99 - $102▼ 38% vs. 2021
2012$71 - $73▼ 55% vs. 2021
2011$71 - $73▼ 55% vs. 2021
2006$63 - $65▼ 60% vs. 2021
2005$63 - $65▼ 60% vs. 2021Compare Mach One Junior models
1 modelsChoose a different build or frame style to see its value.
Overview
About this bike
Entry to BMX Racing shouldn't cost an arm and a leg. The Mach One Junior is made to fit riders 4'4"-4'10".
Specifications
- Subtype
- BMX
- Category
- BMX
- Component Fork
- GT BMX Race, Hi-Ten Steel 1" Steerer, 3/8" Dropouts
- Component Size
- 18.75-inch
- Component Stem
- GT Top Load, 1", 40mm
- Product Family
- Mach One
- Component Chain
- KMC S1
- Component Color
- Gloss Team Blue/GT Yellow/Silver
- Component Frame
- GT Mach One Race MK2, 6061 Alloy, Euro BB, Reverse Dropouts, V-Brakes, 1-1/8" Integrated H/T
- Component Tires
- Kenda Race, 20 x 1-3/8"
- Component Brakes
- Alloy V-type
- Component Pedals
- GT Mini Size Platform, PP Material
- Component Saddle
- GT Uni Mini Padded
- Component Headset
- 1 1/8" Integrated Design, 45X45 Degree Sealed Bearings
- Component Crankset
- GT Alloy Forged 3pc, 152mm, Square Taper, 38T
- Component Seat Post
- 22.2 Integrated
- Component Chainrings
- 38T
- Component Handlebars
- GT Race, Steel, 4"H x 24"w/ 8° Back, 2° Up, 19mm O.D. Cross Bar
- Component Tape Grips
- GT Statement
- Component Bottom Bracket
- Threaded Square Type
- Tires
- Kenda Race, 20 x 1-3/8"
- Crankset
- GT Alloy Forged 3pc, 152mm, Square Taper, 38T
- Pedals
- GT Mini Size Platform, PP Material
- Bottom Bracket
- Threaded Square Type
- Chain
- KMC S1
- Saddle
- GT Uni Mini Padded
- Headset
- 1 1/8" Integrated Design, 45X45 Degree Sealed Bearings
- Stem
- GT Top Load, 1", 40mm
- Brakes
- Alloy V-type
- Chainrings
- 38T
- Fork
- GT BMX Race, Hi-Ten Steel 1" Steerer, 3/8" Dropouts
- Frame
- GT Mach One Race MK2, 6061 Alloy, Euro BB, Reverse Dropouts, V-Brakes, 1-1/8" Integrated H/T
- Handlebars
- GT Race, Steel, 4"H x 24"w/ 8° Back, 2° Up, 19mm O.D. Cross Bar
- Seat Post
- 22.2 Integrated
- Tape/Grips
- GT Statement
- Color
- Gloss Team Blue/GT Yellow/Silver
- Size
- 18.75-inch
What to check when buying used
Inspection
Drivetrain wear
Check chain stretch, cassette teeth, chainrings, and shifting under load before negotiating price.
Inspection
Service history
Ask for service records covering bearings, brakes, drivetrain, and any frame or fork warranty work.