Bicycle Archive · Specification report

2003 GT Power Series Ultra Box

Velopedia Archive ID 38640

Overview

Model year	2003
Brand	GT
Model	Power Series Ultra Box
Bicycle type	BMX
Archive ID	38640
Original MSRP	$749.99
Colors	Avus Blue
Sizes	One

Frameset

Frame construction	TIG-welded
Frame material	6061 T6 aluminum
Fork	GT
Fork material	Chromoly, unicrown crown
Rear shock	N/A

Drivetrain

Component group	N/A
Shifters	N/A
Front derailleur	N/A
Rear derailleur	N/A
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
Handlebar extensions	N/A
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

Manufacturer-published archive data. Confirm exact standards and dimensions before ordering parts or performing service. Generated by Velopedia on October 11, 2026.