CST C638 Road/Street Tire

CST C638 Road/Street Tire

The CST C638 is a wire-bead road tire designed for 26″ and 27″ wheels on cruiser bikes, commuters, and vintage BMX builds. Featuring a grooved centerline for water shedding and textured shoulder tread for cornering grip, this tire balances low rolling resistance with practical all-weather performance. The wire bead construction provides durability and secure rim seating at an affordable price point compared to folding bead alternatives.

Key Features

• Grooved Centerline Tread – Continuous center groove channels water away from the contact patch, reducing hydroplaning risk and maintaining traction on wet pavement
• Textured Shoulder Tread – Side knobs engage during cornering to provide additional grip when leaning through turns or navigating uneven surfaces
• Wire Bead Construction – Steel wire embedded in the bead ensures the tire stays securely seated on the rim under pressure and prevents blow-offs during hard riding or low-pressure situations
• Narrow Profile – Reduces rolling resistance for faster, more efficient pedaling on pavement; well-suited for commuting and long-distance riding where speed matters

Technical Specifications

• Model: C638/Road
• Bead Material: Wire
• Color Options: Black or Gumwall/Black
• Type: Tube-type (requires inner tube)
• Tread Pattern: Grooved centerline with textured shoulders
• Available Sizes:
  • 26″ × 1-3/8″ (Gumwall or Black)
  • 27″ × 1-1/4″ (Gumwall/Black or Black)

Compatibility and Ideal Use Cases

These tires fit 26″ or 27″ rims with corresponding bead seat diameters and require inner tubes (sold separately). Best suited for cruiser bikes, vintage BMX builds, or commuter setups where a narrow, fast-rolling tire is preferred over wider, more aggressive options. The grooved design makes this tire practical for year-round street riding in variable weather conditions. The gumwall color option provides a classic aesthetic for period-correct builds or riders who prefer the vintage look. Not recommended for off-road use, skatepark riding, or applications requiring high-volume tires for impact absorption.