Stoptech 128.34077L Disc Brake Rotor - Front Left

Overview of StopTech Sport Cross-Drilled Disc Brake Rotors

The StopTech Sport Cross-Drilled Disc Brake Rotors (part number 128.34077L) are engineered for BMW models including the 120i, 125i, 128i, 320i, 325i, 325xi, 328i, and 328xi. These rotors provide reliable braking performance with a vented, cross-drilled design that supports heat dissipation and consistent stopping power.

• Cross-drilled surface for improved heat dissipation and brake fade reduction
• Vented rotor design enhances cooling during heavy braking
• Coated hat finish to resist corrosion and extend rotor life
• Floating disc mounting for better rotor alignment and reduced warping
• Compatible with 5-lug bolt pattern and 120 mm bolt circle diameter
• Nominal thickness of 24.000 mm and discard thickness of 22.400 mm
• Overall diameter of 299.8 mm (11.803 inches) suitable for specified BMW models

Detailed Product Description

The StopTech Sport Cross-Drilled Disc Brake Rotors feature a vented design with straight vanes that promote efficient airflow to reduce heat buildup during braking. The cross-drilled surface pattern helps to evacuate gases and debris from the brake pad surface, improving contact and reducing brake fade. The rotor's hat is coated to protect against rust and corrosion, which is critical for maintaining performance over time. With a floating disc mounting system, this rotor allows for slight movement to accommodate thermal expansion and reduce the risk of warping under high-stress conditions.

Designed specifically for BMW 120i, 125i, 128i, 320i, 325i, 325xi, 328i, and 328xi models, the rotor measures 299.8 mm in outside diameter and 24.000 mm nominal thickness, ensuring proper fit and function. The 5-lug bolt pattern with a 120 mm bolt circle diameter matches factory specifications, making installation straightforward.

About StopTech Sport Cross-Drilled Disc Brake Rotors

The StopTech Sport Cross-Drilled Disc Brake Rotors line is designed to offer enhanced braking performance through advanced rotor surface technology and structural design. Cross-drilled rotors like this model improve heat dissipation and reduce brake fade, which is beneficial for both street and light performance driving. The vented rotor construction further aids in cooling, making these rotors suitable for BMW drivers seeking reliable stopping power under varied driving conditions.

Common Applications and Problem Solving

• Reduces brake fade during aggressive or repeated braking
• Improves heat dissipation to prevent rotor warping
• Minimizes corrosion with coated hat finish for longer service life
• Enhances braking consistency on BMW 3 Series and 1 Series models
• Addresses uneven rotor wear and vibration issues

Installation Notes and Tips

• Ensure rotor thickness is above discard thickness of 22.400 mm before installation
• Verify compatibility with BMW 120i, 125i, 128i, 320i, 325i, 325xi, 328i, and 328xi models
• Use proper torque specifications for 5-lug mounting bolts on 120 mm bolt circle
• Inspect brake pads and calipers for wear or damage during rotor replacement
• Allow for proper bedding-in of new rotors to optimize braking performance

Quality Assurance and Warranty

StopTech Sport Cross-Drilled Disc Brake Rotors are manufactured to meet or exceed OEM specifications for fit, form, and function. The rotors undergo rigorous quality control to ensure durability and consistent performance. While specific warranty details are not provided here, StopTech products typically come with a limited warranty against defects in materials and workmanship. Consult product documentation or manufacturer resources for exact warranty terms.