Velopedia Bicycle Archive

2004 Diamondback Viper CX

Original specifications: 20" wheels · legacy reference geometry.

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At a glance

Archive #31728

Model year: 2004
Category: BMX
Original MSRP: $132.00
Sizes: 20"
Colors: Blue Chill
Geometry: Legacy reference
In this record: 21 specifications · archived image · original MSRP · geometry

Original buildHi-tensile steel · 20" wheels

Manufacturer catalog

Published sizes and colors

1 size · 1 color

Manufacturer-published sizes and colors; availability and exact size/color pairings may vary by market or production run.

Published sizes

20"

Published colors

Blue Chill

Frameset

Frame Construction	TIG-welded
Frame Material	Hi-tensile steel
Fork Material	Chromoly, unicrown crown

Drivetrain

Crankset	1-piece 175mm, 44 teeth
Bottom Bracket	Loose ball
BB Shell Width	American
Rear Cogs	1-speed, 16 teeth
Chain	KMC Z410, 1/2 x 1/8"
Pedals	Resin, platform

Brakes

Brakes	Coaster brake, w/Rush Alloy Linear Pull rear brakes, Rush Alloy rear levers

Cockpit & Contact Points

Headset	1 1/8" threadless FSA
Handlebar	Db Expert
Stem	Aluminum
Saddle	Diamondback Padded
Seatpost	Steel, 25.4mm diameter

Wheels & Tires

Hubs	Steel
Rims	Alex C303, 36-hole
Spoke Nipples	Brass nipples
Front Tire	20 x 2.125" Comp III style
Rear Tire	20 x 1.75" Comp III style
Wheel Size	20" wheels

Geometry

Legacy reference · 6 measurements

Historical measurements. Frame size unknown.

All geometry measurementsLegacy reference · 6 measurements

Measurement	Legacy reference
Top tube	488.9 mm
Head-tube angle	74°
Seat-tube angle	70°
Chainstay / rear center	368.3 mm
Wheelbase	957.6 mm
Fork offset / rake	30.5 mm

Frame size not recorded.

Gearing

Lower gears help on climbs. Higher gears suit higher speeds.

Pedal cadence

RPM

Speed units

RPM = pedal turns per minute.

All published sizes44T · 16T · 1-speed

Ratio2.75:1

Estimated speed At 90 RPM Gear14.4 mph

Rear tire: 20×1.75.

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 other gearing

Try your current gearingChanged tires or gears? Calculate your setup.

Your changes apply to this calculation. The archived build stays unchanged.

Gears Drivetrain

Front teeth Smallest rear teeth Largest rear teeth

Use up to three front tooth counts, separated by /. For one rear sprocket, enter the same count twice.

Rear tire

Rear tire marking

Apply the marking on your rear tire or edit its dimensions below. Older or fractional inch sizes need the ISO marking (e.g. 37-590).

Rim diameter (BSD, mm) Tire width (mm)

For 32-622, width is 32 mm and rim diameter is 622 mm. Use the rear tire on mixed-wheel bikes. Leave both fields empty to compare ratios only.

Cadence (RPM) Speed units

Gear, dimension and cadence changes update results automatically.

Gearing comparison
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

Original specifications

Brake pads · Original

Coaster brake

w/Rush Alloy Linear Pull rear brakes, Rush Alloy rear levers

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Seatpost · Original

Steel

25.4mm diameter

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Rims · Original

Alex C303

36-hole

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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" Comp III style, Rear: 20 x 1.75" Comp III style
Drivetrain: 1-speed
Seatpost diameter: 25.4 mm
Bottom bracket / shell: Loose ball · American

Equipment inspection checks 9 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: · Chromoly, unicrown crown

Check paint damage, vent holes and accessible internal surfaces for corrosion. Look for dents, bent tubes and cracking around welded or brazed joints.

Drivetrain

Check drivetrain wear →

Archived: Crankset: 1-piece 175mm, 44 teeth · Bottom bracket: Loose ball · Rear cogs: 1-speed, 16 teeth · Chain: KMC Z410, 1/2 x 1/8"

Check chain tension and chainline, rotate the drivetrain through a full revolution and confirm the rear axle or tensioning hardware cannot slip.
Measure chain wear with a compatible gauge and inspect chainring, cassette or freewheel teeth. A new chain does not rule out wear in the remaining drivetrain.
Turn the cranks slowly, feel for rough bearings and check for side-to-side play. Inspect crank arms, chainring bolts and pedal threads for looseness or damage.

Brakes

Inspect the brakes →

Archived: Brakes: Coaster brake, w/Rush Alloy Linear Pull rear brakes, Rush Alloy rear levers

Inspect pads, cables and housings, then examine both rim braking surfaces for concavity, cracking or heavy wear. Confirm each caliper returns and centers correctly.

Wheels and tires

Check wheels and tires →

Archived: Wheel size: 20" wheels · Rims: Alex C303, 36-hole · Hubs: Steel · Front tire: Front: 20 x 2.125" Comp III style, Rear: 20 x 1.75" Comp III style

Spin both wheels and watch for side-to-side and vertical movement. Check spoke tension, rim condition and hub play.
Inspect both tire casings for cuts, cracking, plugs, bulges or exposed threads and confirm the installed sizes are safe for the rims and available frame and fork clearance.

Controls and contact points

Archived: Headset: 1 1/8" threadless FSA · Handlebar: Db Expert · Stem: Aluminum · Seatpost: Steel, 25.4mm diameter · Saddle: Diamondback Padded · Pedals: Resin, platform

Apply the front brake and rock the bike to check for headset play or notchiness. Inspect the stem, handlebar and clamp zones, then confirm every fastener and control is secure.
Check that the seatpost moves for adjustment and that the saddle, post and clamp hold securely without cracks, severe corrosion or damaged hardware.

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Specifications are presented as a reference. Components may vary by market, size, production run, or later manufacturer revisions.

2004 Diamondback Viper CX