Bicycle Archive · Specification reportBicycle Archive · Specification report1999 GT Bump · 2000 GT Bump
| Specification | 1999 GT Bump | 2000 GT Bump |
|---|---|---|
| Overview | ||
| Model year | 1999 | 2000 |
| Brand | GT | GT |
| Model | Bump | Bump |
| Bicycle type | Freestyle/jumping | Freestyle/jumping |
| Archive ID | 86541 | 46212 |
| Original MSRP | $316.99 | $380.00 |
| Colors | Atomic Blue, Khaki | Cheesy, High Voltage Black |
| Frameset | ||
| Frame construction | Welded | TIG-welded |
| Frame material | Chromoly | Chromoly |
| Fork | GT | GT |
| Fork material | Chromoly, oversize, 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 1-piece chromoly, 44 teeth | GT 3-piece chromoly, 44 teeth |
| Bottom bracket | One piece | One piece |
| Rear cogs | 1-speed, 16 teeth | 1-speed, 16 teeth |
| Chain | 1/2 x 1/8" | KMC, 1/2 x 1/8" |
| Pedals | GT aluminum platform | GT aluminum platform |
| Brakes | ||
| Brakes | Dia-Compe 990 rear brakes, Dia-Compe MX-97 rear levers | DiaTech 996 U-Brake rear brakes, Dia-Compe MX-101 rear levers |
| Cockpit & contact points | ||
| Headset | 1 1/8" threadless Aheadset SX-1 | 1 1/8" threadless Aheadset SB-1 w/SST Oryg detangler |
| Handlebar | GT | GT Freestyle |
| Handlebar extensions | N/A | Not included |
| Stem | GT Piston | GT Johnson |
| Saddle | GT | GT |
| Seatpost | GT chromoly micro-adjust, 31.8mm diameter | GT aluminum micro-adjust, 31.6mm diameter |
| Wheels & tires | ||
| Hubs | GT Mohawk | GT Mohawk |
| Rims | Weinmann ZAC-X, 48-hole | Weinmann ZAC-X, 48-hole |
| Spokes | Steel, 2.0mm straight gauge | 2.0mm |
| Spoke nipples | Brass nipples | Brass nipples |
| Front tire | 20 x 2.125" Powerlite Retro-Tread | 20 x 2.125" Powerlite Retro Tread |
| Rear tire | 20 x 1.75" Powerlite Retro-Tread | 20 x 1.75" Powerlite Retro Tread |
| 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 | 1999 GT Bump | 2000 GT Bump |
|---|---|---|
| Selected size / position | — | Legacy reference |
| Head-tube angle | — | 73.5° |
| Seat-tube angle | — | 70° |
| Chainstay / rear center | — | 381 mm |
| Wheelbase | — | 967.5 mm |
Manufacturer-published archive data. Confirm exact standards and dimensions before ordering parts or performing service. Generated by Velopedia on November 13, 2026.