Built for freestyle fun, the Diamondback Viper X 20" BMX bike is ready to hit the BMX park.
- Beefy steel frame and fork withstand the force of freestyle antics
- 44-tooth steel cranks and 18-tooth cog make up the rugged single-speed drivetrain
- Rush U rear brake provides stopping power when needed
- Sturdy BMX 20 in. wheels are outfitted with Comp III style tires; tire on front is wider than tire on rear
- Closeout
- NOTE: Specs and images are subject to change based on component availability
Imported.
This bike comes with Coast to Coast Support, which includes:
New bikes go through a normal break-in period, after which they should be readjusted. All bicycles sold at REI include free adjustments for one year after purchase date—as many times as you need. Included: derailleur and brake adjustments, lateral wheel truing, hub and headset bearing adjustments, tire inflation and chain lubrication. Not included: replacement or installation of new components or accessories, any other services. Call your local REI Co-op Bike Shop for more information.
View all Diamondback- 1 year of free adjustments (see more below)
- In-store bike assembly
- Pickup in store or curbside
- Bike experts available at 170+ bike shops
- 20% off shop services
- Free tubes with purchase of flat tire repair (Co-op Cycles brand tubes only; tube must be installed at time of purchase)
New bikes go through a normal break-in period, after which they should be readjusted. All bicycles sold at REI include free adjustments for one year after purchase date—as many times as you need. Included: derailleur and brake adjustments, lateral wheel truing, hub and headset bearing adjustments, tire inflation and chain lubrication. Not included: replacement or installation of new components or accessories, any other services. Call your local REI Co-op Bike Shop for more information.
| Best Use | Cycling |
|---|---|
| Frame | High-tensile steel with chromoly seat tube |
| Bike Suspension | No Suspension |
| Fork | High-tensile steel |
| Crankset | 175mm chromoly, 1-piece / (sprocket) steel 44t |
| Bottom Bracket | Loose ball |
| Rear Cogs | 18T |
| Brake Type | Rim |
| Brakes | Rush U-brake |
| Brake Levers | Rush 2 finger |
| Rims | Aluminum |
| Front Hub | Aluminum |
| Rear Hub | Aluminum |
| Wheel Size | 20 inches |
| Tires | Comp III style 20 x 2.125 (front), 1.75 (rear) |
| Handlebar Shape | Riser Bar |
| Handlebar | 2-piece hi-ten steel 26" wide x 7.75" rise |
| Stem | 4 bolt alloy top load |
| Seat Post | Steel micro adjust |
| Saddle | Diamondback padded BMX |
| Pedals | Resin platform |
| Headset | 1 in. threaded |
| Chain | KMC Z410 |
| Weight | Unavailable |
| Gender | Boys' |
Diamondback Bikes (833889)
| 20 IN | |
|---|---|
| Effective Top Tube | 20.5 |
| Head Tube Angle (degrees) | 74 |
| Seat Tube Angle (degrees) | 71 |
| Chainstay | 15.25 |
Sizing Notes
Measurements are stated in inches unless otherwise indicated.
How we measure bikes
- Standover Height Standover Height is a measurement from the ground to the top of the top tube, measured at the midpoint of the top tube.
- Reach Reach is the horizontal distance from the center of the cranks to the center of the head tube, measured at head tube level.
- Stack Stack is the vertical distance from the center of the cranks to the center of the head tube, measured to the top of the head tube.
- Effective Top Tube Effective top tube is the distance from the center of the head tube to the center of the seat tube/seat post, measured parallel to the ground.
- Seat Tube Center to Top Seat Tube length is the measurement of the seat tube, from the center of the cranks to the top of the seat tube.
- Head Tube Length Head Tube Length is measured from the bottom to the top of the head tube.
- Head Tube Angle Head Tube Angle is the acute angle between the head tube and the ground (measured towards the rear of the bike)
- Seat Tube Angle Seat Tube Angle is the acute angle between the seat tube and the ground (measured towards the rear of the bike).
- Bottom Bracket Height Bottom Bracket Height is a measurement taken vertically from the ground up to the center of the cranks.
- Wheelbase Wheelbase is the measurement from the center of the front axle to the center of the rear axle.
- Chainstay Length Chainstay Length is the measurement from the center of the cranks to the center of the rear axle.
- Fork Offset Fork Offset, or rake, is the distance from the front axle to a line drawn parallel to the center of the head tube or steering axis.