Inspection
Frame condition
Inspect the frame, fork, welds, and high-stress areas for cracks, dents, or prior repairs.
GT
2021 GT Grunge 20"
Previous used estimate
$125 - $129
Actual value depends on condition, size, and local demand.
Value Guide market data · 2021 GT Grunge 20"
12-month projected trend
9%
Direction and magnitude, not judgment
vs. category average
4%
Holds value better than category avg
Price over time - 2021 GT Grunge 20"
Values based on actual sales data. Enter your bike's specifics to get a precise valuation.
All Grunge model years
Compare Grunge 20" models
1 modelsChoose a different build or frame style to see its value.
Overview
About this bike
Even our kids' bikes are built right from the ground up—perfectly proportioned lightweight alloy frame, easy-riding low-slung design, and handling that makes every ride a breeze. Durable 1pc cranks, all-terrain tires, 2pc bars and even a numberplate FTW. - Improved Geometry bikes with the LegitFit system feature geometry adjustments to improve ergonomics for youth statures. The result: Increased stability, comfort and confidence for a wider range of riders. - Easier Pedaling bikes with the LegitFit system have their pedal positions moved slightly forward. The result: Makes it easier to pedal. - Better Positioning bikes with the LegitFit system have narrower crank and pedal positions that match the width of a child’s hips. The result: A stronger, more natural pedal stroke.
Specifications
- Subtype
- 20-inch
- Category
- Kids
- Component Fork
- GT Hi-Ten Steel, 1" Threaded Steerer
- Component Hubs
- Front: Steel, Nutted Axle Rear: Steel, Nutted Axle, Coaster Brake
- Component Size
- 20-inch
- Component Stem
- 2-Bolt Alloy Top, Steel Quill
- Product Family
- Grunge
- Component Chain
- KMC S1, 1/2" x 1/8"
- Component Color
- Gloss Battleship Gray/Blue/Black, Gloss Blue/Orange/Yellow/White
- Component Frame
- 20" GT LegitFit Design, Alloy
- Component Tires
- GT 20 x 1.95"
- Component Brakes
- Coaster Rear, Rear Alloy VBrake
- Component Pedals
- Jr. BMX Design, Resin
- Component Saddle
- GT 1-piece
- Component Headset
- 1" Threaded, Steel
- Component Crankset
- Forged One-Piece Type, 127mm
- Component Chainrings
- 32T
- Component Handlebars
- Steel Riser Bar, 176mm Rise, 580mm Width
- Component Tape Grips
- 120mm Closed End
- Component Bottom Bracket
- Steel, Ball Type
- Component Accessories Extras
- Fender, Bar, Stem Pad
- Hubs
- Front: Steel, Nutted Axle Rear: Steel, Nutted Axle, Coaster Brake
- Tires
- GT 20 x 1.95"
- Crankset
- Forged One-Piece Type, 127mm
- Pedals
- Jr. BMX Design, Resin
- Bottom Bracket
- Steel, Ball Type
- Chain
- KMC S1, 1/2" x 1/8"
- Saddle
- GT 1-piece
- Headset
- 1" Threaded, Steel
- Stem
- 2-Bolt Alloy Top, Steel Quill
- Accessories & Extras
- Fender, Bar, Stem Pad
- Brakes
- Coaster Rear, Rear Alloy VBrake
- Chainrings
- 32T
- Fork
- GT Hi-Ten Steel, 1" Threaded Steerer
- Frame
- 20" GT LegitFit Design, Alloy
- Handlebars
- Steel Riser Bar, 176mm Rise, 580mm Width
- Tape/Grips
- 120mm Closed End
- Color
- Gloss Blue/Orange/Yellow/White
- Size
- 20-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.