20x4.0 Bike Inner Tubes - Schrader Valve, Butyl Rubber - Pack of 2

Key Features

• Package Contents: Two (2) inner tubes
• Material: High-quality butyl rubber for superior air retention and puncture resistance
• Valve Type: Schrader (AV)
• Valve Length: 32mm
• Construction: Heavy-duty, increased thickness for durability
• ETRTO Size: 89/102-406

Replaces / Cross-Reference Part Numbers

• This product is a direct replacement for inner tubes used in tires marked with the following sizes:
• 20 x 3.5
• 20 x 3.6
• 20 x 3.8
• 20 x 4.0

Compatibility & Fitment

• Tire Diameter: 20 inches
• Tire Width Range: 3.5 inches to 4.0 inches
• Valve Requirement: Fits bicycle rims drilled for Schrader valves
• Primary Application: Fat tire bikes, electric bicycles (E-bikes)

When to Replace

• Visible punctures, cuts, or abrasions on the tube surface.
• Consistent loss of air pressure after inflation.
• Tube develops a bulge or deformity.
• Valve stem is cracked, damaged, or leaking at the base.
• After a severe impact or pinch flat, as a preventative measure.

Installation Tips

• Before installing, carefully inspect the interior of the tire for thorns, glass, or other sharp debris.
• Confirm the rim strip is in good condition and correctly covers all spoke holes.
• Lightly inflate the new tube before inserting it into the tire to give it shape and prevent pinching under the tire bead.
• Ensure the valve stem is straight and perpendicular to the rim.
• Seat the tire bead evenly on both sides of the rim before inflating to the recommended pressure.
• Inflate to the PSI specified on the tire's sidewall, not on the inner tube.