Stoptech 127.34109L Disc Brake Rotor - Rear Left

StopTech Sport Cross-Drilled & Slotted Disc Brake Rotors Overview

The StopTech Sport Cross-Drilled & Slotted Disc Brake Rotor (Part Number 127.34109L) is engineered for BMW 135i and 135is models. Designed to enhance braking performance, this vented rotor features a slotted and drilled surface to improve heat dissipation and maintain consistent stopping power under demanding conditions.

• Compatible with BMW 135i and 135is
• Part Number: 127.34109L
• Cross-drilled and slotted surface for improved cooling and debris removal
• Vented rotor design with straight vane style for efficient heat management
• Coated hat finish to resist corrosion
• Nominal thickness: 0.858 inches (21.8 mm)
• Outside diameter: 12.756 inches (324 mm)
• Mounting bolt pattern: 5 lug holes, 4.724 inches (120 mm) bolt circle diameter

Detailed Product Description

This disc brake rotor is part of the StopTech Sport Cross-Drilled & Slotted Disc Brake Rotors line, which focuses on delivering enhanced braking performance through advanced rotor surface technology. The cross-drilled and slotted design helps to evacuate gases, dust, and water from the braking surface, reducing brake fade and improving pad bite. The vented rotor with straight vanes promotes airflow to dissipate heat efficiently, which is critical for maintaining braking consistency during spirited driving or track use.

The rotor features a coated hat finish that provides corrosion resistance, extending the rotor's service life. With a nominal thickness of 0.858 inches (21.8 mm) and a discard thickness of 0.803 inches (20.4 mm), this rotor meets strict specifications for durability and performance. The overall height is 3.035 inches (77.1 mm), and the center hole diameter is 2.953 inches (75 mm), ensuring proper fitment on compatible BMW 135i and 135is vehicles.

Common Applications and Problem Solving

• Reduces brake fade during aggressive driving or track conditions
• Improves heat dissipation to prevent rotor warping
• Enhances braking response and pad bite with slotted and drilled surface
• Minimizes brake dust buildup for cleaner braking components
• Resists corrosion with coated hat finish for longer rotor life

Installation Notes and Tips

• Ensure compatibility with BMW 135i and 135is models before installation
• Check rotor thickness and discard thickness to confirm replacement timing
• Use proper torque specifications for the 5 lug bolts on the 120 mm bolt circle
• Inspect brake pads and hardware during rotor replacement for optimal performance
• Follow manufacturer guidelines for bedding-in new rotors and pads

Quality Assurance and Warranty

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