Bicycle Archive · Specification report

Bicycle comparison

2009 GT Bump · 2008 GT Bump

Specification	2009 GT Bump	2008 GT Bump
Overview
Model year	2009	2008
Brand	GT	GT
Model	Bump	Bump
Bicycle type	BMX	BMX
Archive ID	18807	13609
Original MSRP	$399.99	$279.99
Colors	Light Green, Purple	Off White/Orange, Navy/White
Sizes	21.1" TT	One size fits all
Frameset
Frame construction	TIG-welded	TIG-welded
Frame material	Chromoly main triangle	GT cro-moly BMX dirt/street design
Fork	GT Dirt/Street	GT BMX design
Fork material	Chromoly, unicrown crown	Chromoly, unicrown crown
Rear shock	N/A	N/A
Drivetrain
Component group	BMX	BMX
Shifters	N/A	N/A
Front derailleur	N/A	N/A
Rear derailleur	N/A	N/A
Crankset	GT Tubular Cr-Mo 3pc., 33 teeth	GT Tubular Cr-Mo 3pc.
Bottom bracket	Mid BB	Ball type with 8 spline Cr-Mo axle
Cassette	Cassette cog	—
Rear cogs	1-speed, 12 teeth	1-speed, 12 teeth
Chain	KMC Z510	KMC Z410
Pedals	GT Dirt/Street platform	GT Dirt/Street platform
Brakes
Brakes	Tektro 907A U-brake rear brakes, Tektro 274A rear levers	N/A front/Tektro 907A rear brakes, Tektro 274A rear levers
Cockpit & contact points
Headset	1 1/8" Tange Seiki Fatty 22	1 1/8" Tange Seiki Fatty 22
Handlebar	GT dirt/street Cr-mo	GT dirt/street Cr-mo
Handlebar extensions	Not included	Not included
Stem	GT FS design	GT FS design
Saddle	GT Slim	BMX mini street
Seatpost	Aluminum micro-adjust double bolt	Aluminum micro-adjust
Wheels & tires
Hubs	Front: GT aluminum sealed, Rear: GT sealed cassette	Front: GT aluminum sealed, Rear: GT sealed cassette
Rims	Alienation PBR, 32-hole/36-hole	36-hole
Spokes	Stainless, 14ga. (2.0mm)	14ga. (2.0mm)
Spoke nipples	Brass	Brass nipples
Front tire	20 x 2.125" Kenda K-Rad	20" Kenda K-Rad
Rear tire	20 x 2.10" Kenda Kiniption	20" Kenda Konxsion
Wheel size	20" wheels	20" wheels

Manufacturer-published archive data. Confirm exact standards and dimensions before ordering parts or performing service. Generated by Velopedia on November 13, 2026.