Centric 121.34104 Disc Brake Rotor - Front

Overview of Centric C-TEK Standard Disc Brake Rotor 121.34104

The Centric C-TEK Standard Disc Brake Rotor 121.34104 is engineered for reliable braking performance on BMW 135i and 135is models. Designed as a vented rotor with a smooth surface, it offers consistent heat dissipation and stable stopping power under normal driving conditions.

• Compatible with BMW 135i and 135is vehicles
• Vented disc brake rotor design for improved cooling
• Overall diameter of 338 mm (13.307 inches)
• Nominal thickness of 25.8 mm (1.016 inches) with discard thickness at 24.4 mm (0.961 inches)
• Floating disc mounting with straight vane style for efficient airflow
• 5 lug holes with 120 mm bolt circle diameter
• Center hole diameter of 79 mm (3.110 inches)
• Weight approximately 9.82 kg (21.6 lbs)
• ABS tone ring not included

About the C-TEK Standard Disc Brake Rotors Line

The C-TEK Standard Disc Brake Rotors line by Centric focuses on delivering OEM-equivalent replacement rotors that meet factory specifications. This product line emphasizes precise fitment and consistent braking performance, making it suitable for drivers seeking dependable rotor replacements without modifications. The 121.34104 rotor maintains the original equipment dimensions and vented design to ensure proper heat management and rotor longevity on BMW 135i and 135is models.

Technical Details and Specifications

This disc brake rotor features a vented design with straight vanes to promote effective heat dissipation during braking. The rotor’s nominal thickness is 25.8 mm, with a discard thickness of 24.4 mm, indicating when replacement is necessary to maintain safe braking. The overall height measures 73 mm, and the rotor mounts using a floating disc system with a 5-lug pattern on a 120 mm bolt circle diameter. The smooth surface type supports consistent pad contact and braking feel. Note that this rotor does not include an ABS tone ring or bearings.

Applications and Problem Solving

• Replacement for worn or warped rotors on BMW 135i and 135is
• Addresses brake pulsation caused by uneven rotor surfaces
• Restores proper rotor thickness for safe braking performance
• Improves heat dissipation to reduce brake fade during normal driving
• Compatible with factory brake components requiring vented rotors

Installation Notes and Tips

Ensure the rotor thickness is measured before installation to confirm it meets or exceeds the nominal thickness of 25.8 mm. Clean the rotor surface to remove any protective coatings or contaminants prior to mounting. Use proper torque specifications for the 5 lug nuts on the 120 mm bolt circle diameter. Since this rotor does not include bearings or an ABS tone ring, verify compatibility with your vehicle’s existing components. It is recommended to replace brake pads simultaneously for optimal braking performance.

Quality Assurance and Warranty

Centric’s C-TEK Standard Disc Brake Rotors are manufactured to meet or exceed OEM standards for fit, form, and function. While specific warranty details for part number 121.34104 are not provided here, Centric typically offers limited warranties covering defects in materials and workmanship. Refer to Centric’s official documentation for complete warranty information.