
Velopedia Bicycle Archive
2003 GT Power Series Ultra Box
Original specifications: 20" wheels.
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At a glance
- Model year
- 2003
- Category
- BMX
- Original MSRP
- $749.99
- Sizes
- One
- Colors
- Avus Blue
- In this record
- 22 specifications · archived image · original MSRP
- Archive ID
- 38640
Model history 5 other years
Original build6061 T6 aluminum · 20" wheels
Frameset
| Frame Construction | TIG-welded |
|---|---|
| Frame Material | 6061 T6 aluminum |
| Fork | GT |
| Fork Material | Chromoly, unicrown crown |
Drivetrain
| Crankset | GT 3-piece chromoly, 44 teeth |
|---|---|
| Bottom Bracket | Sealed cartridge |
| BB Shell Width | Euro |
| Rear Cogs | 1-speed, 16 teeth |
| Chain | KMC Z610HX, 1/2 X 3/16" |
| Pedals | GT BMX Design Aluminum |
Brakes
| Brakes | Tektro BX-25 rear brakes, Tektro BX-2 rear levers |
|---|
Cockpit & Contact Points
| Headset | 1 1/8" threadless FSA Orbit Z |
|---|---|
| Handlebar | GT BMX |
| Stem | GT Piston |
| Saddle | GT Dropnose |
| Seatpost | Aluminum micro-adjust, 31.6mm diameter |
Wheels & Tires
| Hubs | GT Rhythm System II |
|---|---|
| Rims | GT Rhythm System |
| Spokes | Stainless steel, 14ga. (2.0mm) straight gauge |
| Spoke Nipples | Aluminum nipples |
| Front Tire | 20 x 2.125" IRC Siren |
| Wheel Size | 20" wheels |
Parts & serviceability
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Bike-specific inspection checklist 19 checks based on 5 archived component groups Open checklistClose checklist
This checklist uses the archived equipment for this bike. It cannot confirm the condition, service history or later component changes of the example in front of you.
Identity and fit
Follow the full used-bike inspection order →Archived: 2003 GT Power Series Ultra Box · BMX · Published sizes: One
Frame and fork
Inspect the frame and fork →Archived: Frame: TIG-welded · Fork: GT · Chromoly, unicrown crown
Drivetrain
Check drivetrain wear →Archived: Crankset: GT 3-piece chromoly, 44 teeth · Bottom bracket: Sealed cartridge · Rear cogs: 1-speed, 16 teeth · Chain: KMC Z610HX, 1/2 x 3/16"
Brakes
Inspect the brakes →Archived: Brakes: Tektro BX-25 rear brakes, Tektro BX-2 rear levers
Wheels and tires
Check wheels and tires →Archived: Wheel size: 20" wheels · Rims: GT Rhythm System · Hubs: GT Rhythm System II · Front tire: 20 x 2.125" IRC Siren
Controls and contact points
Archived: Headset: 1 1/8" threadless FSA Orbit Z · Handlebar: GT BMX · Stem: GT Piston · Seatpost: Aluminum micro-adjust, 31.6mm diameter · Saddle: GT Dropnose · Pedals: GT BMX Design Aluminum
Before and during the test ride
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Specifications are presented as a reference. Components may vary by market, size, production run, or later manufacturer revisions.




