Bicycle Archive · Specification reportBicycle Archive · Specification report2004 GT Bump · 2005 GT Bump
| Specification | 2004 GT Bump | 2005 GT Bump |
|---|---|---|
| Overview | ||
| Model year | 2004 | 2005 |
| Brand | GT | GT |
| Model | Bump | Bump |
| Bicycle type | Freestyle/jumping | Freestyle/jumping |
| Archive ID | 31429 | 93627 |
| Original MSRP | $249.99 | $269.99 |
| Colors | Red, Silver | Deep Artic Blue, Madness Pewter |
| Sizes | One | — |
| Frameset | ||
| Frame construction | TIG-welded | TIG-welded |
| Frame material | Chromoly main triangle/hi-tensile steel rear stays | Chromoly |
| Fork | GT | GT |
| Fork material | Chromoly, unicrown crown | Chromoly, unicrown crown |
| Rear shock | N/A | N/A |
| Drivetrain | ||
| Component group | N/A | N/A |
| Shifters | N/A | N/A |
| Front derailleur | N/A | N/A |
| Rear derailleur | N/A | N/A |
| Crankset | GT 3-piece chromoly, 39 teeth | GT tubular chromoly, 39 teeth |
| BB shell width | American | — |
| Rear cogs | 1-speed, 14 teeth | 1-speed, 14 teeth |
| Chain | KMC 410, 1/2 x 3/16" | KMC Z410, 1/2 x 1/8" |
| Pedals | GT Johnson design | GT Dirt/Street |
| Brakes | ||
| Brakes | Tektro 907A U-brake rear brakes, Tektro 274A rear levers | Tektro 907AD rear brakes, Tektro 274A rear levers |
| Cockpit & contact points | ||
| Headset | 1 1/8" threadless Victor VP-A74F | 1 1/8" threadless Tange Seiki Fatty 22 |
| Handlebar | GT BMX | Chromoly 2-piece |
| Handlebar extensions | N/A | — |
| Stem | GT Piston | GT Johnson III |
| Saddle | GT Jr Jump, 9mm rails | GT-6 Original |
| Seatpost | Steel micro-adjust | Aluminum micro-adjust |
| Wheels & tires | ||
| Hubs | Aluminum, 14mm axle | Aluminum, 3/8" axle |
| Rims | Alex G22, 36-hole | Alex G22 |
| Spokes | Stainless steel, 14ga. (2.0mm) straight gauge | 14ga. (2.0mm) straight gauge |
| Spoke nipples | Brass nipples | Brass nipples |
| Front tire | 20 x 2.20" GT 1453 | 20 x 2.20" GT 1453 |
| Rear tire | 20 x 2.10" GT LP-4 | 20 X 2.10" GT LP-IV |
| Wheel size | 20" wheels | 20" wheels |
One selected size or frame position per bicycle, matching the comparison dropdown choices used when Print / PDF was opened.
| Measurement | 2004 GT Bump | 2005 GT Bump |
|---|---|---|
| Selected size / position | Legacy reference | — |
| Head-tube angle | 74.5° | — |
| Seat-tube angle | 71° | — |
| Chainstay / rear center | 355.6 mm | — |
Manufacturer-published archive data. Confirm exact standards and dimensions before ordering parts or performing service. Generated by Velopedia on November 15, 2026.