Ratio2.75:1
Estimated speed At 90 RPM
Gear
Rear tire: 20×1.75.
Velopedia Bicycle Archive
2004 GT Power Series Pro
Original specifications: 20" wheels · legacy reference geometry.
Planning to sell? Draft your listing
At a glance
Archive #31447- Model year
- 2004
- Category
- BMX
- Original MSRP
- $249.99
- Sizes
- Pro
- Colors
- Blue
- Geometry
- Legacy reference
- In this record
- 22 specifications · archived image · original MSRP · geometry
Model history 8 other years
Browse other years
Compare side by side
Identification clues
2004 archived details
- Published colors
- Blue
- Frame
- 6061 T6 aluminum
- Original equipment
- N/A
Clues, not proof of model year. Colors vary and components may have been replaced.
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 one-piece, 44 teeth |
|---|---|
| BB Shell Width | American |
| Rear Cogs | 1-speed, 16 teeth |
| Chain | KMC Z30, 1/2 x 1/8" |
| Pedals | GT BMX Design Aluminum |
Brakes
| Brakes | Tektro 924AL rear brakes, Tektro 319A rear levers |
|---|
Cockpit & Contact Points
| Headset | 1 1/8" threadless Victor VP-A74F |
|---|---|
| Handlebar | GT BMX |
| Stem | GT Piston |
| Saddle | GT BMX |
| Seatpost | Aluminum micro-adjust, 27.0mm diameter |
Wheels & Tires
| Hubs | GT BMX |
|---|---|
| Rims | Alex G303, 36-hole |
| Spokes | Steel, 14ga. (2.0mm) straight gauge |
| Spoke Nipples | Brass nipples |
| Front Tire | 20 x 2.125" IRC Siren |
| Rear Tire | 20 x 1.75" IRC Siren |
| Wheel Size | 20" wheels |
No specifications match. Try a component name or clear your search.
Geometry
Historical measurements. Frame size unknown.
Reference drawing
Size
Measurement
Measurement
—
Select an available measurement to locate it on the frame.
All geometry measurementsLegacy reference · 4 measurements
| Measurement | Legacy reference |
|---|---|
| Top tube | 508 mm |
| Head-tube angle | 74.5° |
| Seat-tube angle | 70.5° |
| Chainstay / rear center | 368.3 mm |
Frame size not recorded.
Gearing
Lower gears help on climbs. Higher gears suit higher speeds.
RPM
RPM = pedal turns per minute.
How it works
Ratio = front teeth ÷ rear teeth. Hub gears also include the hub’s internal ratio. A 400% range means the highest ratio is four times the lowest.
Speeds are estimates from tire size and pedal cadence. Actual speeds vary.
Try your current gearingChanged tires or gears? Calculate your setup.
Your changes apply to this calculation. The archived build stays unchanged.
Gearing results
| Measure | Original | Your setup |
|---|---|---|
| Lowest ratio | — | — |
| Highest ratio | — | — |
| Total range | — | — |
| Lowest-gear speed | — | — |
| Highest-gear speed | — | — |
Speeds are estimates. These calculations do not establish component compatibility or available tire clearance.
Parts & serviceability
Find replacement parts
KMC Z30
1/2 x 1/8"
20 x 2.125" IRC Siren
Aluminum micro-adjust
27.0mm diameter
More parts (1)Fewer parts
Alex G303
36-hole
Based on the original build. Check fit and installed parts before ordering. Affiliate links may earn Velopedia a commission. As an Amazon Associate I earn from qualifying purchases.
Parts and service referenceQuick reference before buying parts
Archived specifications for reference. Check the fitted parts before ordering.
- Front tire
- Front: 20 x 2.125" IRC Siren, Rear: 20 x 1.75" IRC Siren
- Drivetrain
- 1-speed
- Seatpost diameter
- 27 mm
- Bottom bracket / shell
- American
Equipment inspection checks 10 checks based on 5 archived component groups Open equipment checksClose equipment checks
Checks selected from the archived equipment. Confirm what is fitted today. This is not a complete safety inspection; use the full inspection guide before test riding.
Full used-bike inspection guide →
Frame and fork
Inspect the frame and fork →Archived: Frame: TIG-welded · Fork: GT · Chromoly, unicrown crown
Drivetrain
Check drivetrain wear →Archived: Crankset: GT one-piece, 44 teeth · Rear cogs: 1-speed, 16 teeth · Chain: KMC Z30, 1/2 x 1/8"
Brakes
Inspect the brakes →Archived: Brakes: Tektro 924AL rear brakes, Tektro 319A rear levers
Wheels and tires
Check wheels and tires →Archived: Wheel size: 20" wheels · Rims: Alex G303, 36-hole · Hubs: GT BMX · Front tire: Front: 20 x 2.125" IRC Siren, Rear: 20 x 1.75" IRC Siren
Controls and contact points
Archived: Headset: 1 1/8" threadless Victor VP-A74F · Handlebar: GT BMX · Stem: GT Piston · Seatpost: Aluminum micro-adjust, 27.0mm diameter · Saddle: GT BMX · Pedals: GT BMX Design Aluminum
Have you owned this model?Help preserve its real-world history by sharing your owner experience.
Share the details that would help another rider understand how this model fits, rides and holds up over time. Velopedia reviews every contribution before publication.
Already contributed? Send me a fresh private edit link
For privacy, Velopedia shows the same confirmation whether or not an experience exists.
Checking current listings…
Find this bike on eBay
Search eBay US; check the model year, size and installed components. We may earn a commission from purchases.
Specifications are presented as a reference. Components may vary by market, size, production run, or later manufacturer revisions.