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Ksport

Supercomp 421mm Big Brake Kit

$6,098.40 $5,266.80 Save $831.60

SKU: BKBM101-971CO

Special Order
Free Shipping over $200
$100 Minimum Order
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The Ksport Supercomp Big Brake Kit is a front big brake system designed for the BMW E70 X5. It features a 421mm rotor diameter and a 36mm rotor thickness. This kit provides enhanced stopping power and aims to reduce brake fade.

Built with a lightweight SuperComp caliper forged from aircraft quality billet aluminum, this kit incorporates larger pistons and a differential bore configuration for superior performance. It includes high-temperature seals, titanium brake pad retainer clips, and stainless-steel wear plates. The opposed piston caliper design improves pad wear and rigidity, while the stainless-steel brake lines prevent expansion under pressure. Each caliper requires four brake pads due to its size. The kit also features a 2-piece floating disc assembly to reduce weight and manage thermal stresses, with unique slot designs for noise reduction and debris expulsion. Cross-drilled rotors are recommended for daily driven vehicles, while slotted rotors are suited for track use. This product is made to order and non-refundable.
Show original supplier description
The Ksport Supercomp Big Brake Kit offers a significant upgrade in stopping power for your BMW E70 X5. The SuperComp caliper, forged from aircraft-quality billet aluminum, is extremely lightweight (just over 7 lbs each) and features a differential bore configuration with larger pistons compared to standard calipers. It includes high-temperature seals, titanium brake pad retainer clips, and stainless-steel brake pad wear plates. The opposed piston design enhances caliper rigidity and improves pad wear, while DOT-compliant stainless-steel braided brake lines ensure a firmer pedal feel and quicker response. Due to the caliper's substantial size, each unit utilizes four brake pads. The kit includes a 2-piece floating disc assembly, which reduces both rotating and unsprung weight, and helps mitigate thermal stresses that can cause warping. The unique rotor slot design aids in noise reduction and efficiently expels gas and pad debris. Customers can choose between cross-drilled rotors, recommended for daily driving due to cooler operation, or slotted rotors, preferred for track applications. Both rotor types offer increased "bite" and continuously refresh the pad surface. This kit is made to order and is non-refundable. Standard equipment includes Ksport SC5 Street Pads, designed for optimal performance in street and occasional track conditions. An optional upgrade to Ksport RC5 Race Pads, constructed from carbon metallic material for extreme track conditions, is available. The SC5 pads offer reduced brake dust and noise compared to race pads, with an average coefficient of friction between 0.46 and 0.53. The RC5 pads are optimized for temperatures between 482°F – 1472°F and are not recommended for street use. The kit comes with CNC-machined carbon steel caliper brackets specifically designed for easy bolt-on installation and a 12-month limited warranty against manufacturer defects.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

BrandKsport
Part NumberBKBM101-971CO
CategoryBrakes

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