Flex Black Rear Brake Replacement: Step-by-Step Guide

By Micro Kickboard | Published: 2026-10-31

Category: How-to Guides

Replace the rear brake on your Flex Black scooter with Micro Kickboard part #1575. Follow these steps to restore safe stopping power and avoid common mistakes.

Quick answer

Replace the complete rear brake assembly on your Flex Black with Micro Kickboard part #1575. The job takes about 15–20 minutes with basic tools, and no special expertise is needed.

When to replace rather than adjust

If your Flex Black rear brake feels loose, stops poorly, or makes grinding noises, first check the brake adjustment and pad wear. A simple adjustment or pad cleaning may solve the problem. But if the brake assembly is cracked, the spring is broken, or the mounting holes are elongated, replacement is the safer choice. The complete assembly (part #1575) includes all brake components, so you avoid hunting for individual pieces.

Tools and preparation

You will need a 4 mm and 5 mm hex key, a Phillips screwdriver, and a clean rag. Work on a flat surface with the scooter turned off and the battery removed if your model is electric. Have the new brake assembly and any included hardware within reach before you start.

Step-by-step rear brake replacement

Remove the old brake: Unscrew the mounting bolts with a 5 mm hex key and disconnect the brake cable from the lever. Keep the bolts and any spacers together; you may need them for the new assembly. Lay out the old parts in order so you can match them during reassembly.
Transfer the cable and hardware: If the new brake does not include a cable, slide the old cable through the new brake arm and secure it with the pinch bolt. Reuse the original mounting bolts if they are in good condition. Check that the cable slides freely and the housing is not kinked.
Mount the new brake assembly: Position the new brake on the frame and hand-tighten the mounting bolts. Ensure the brake pad aligns with the rear wheel rim or hub surface, then tighten the bolts fully. Spin the wheel to confirm the pad does not rub before tightening.
Adjust brake tension: Turn the barrel adjuster on the brake lever to set the pad close to the rim (about 1–2 mm gap). Squeeze the lever a few times to check that the brake engages smoothly and releases fully. The wheel should spin freely when the lever is released.
Test and fine-tune: Ride slowly in a safe area and test the brake at low speed. If stopping power is weak, increase cable tension slightly. If the brake squeals, clean the pad and rim with a rag and re-check alignment. Repeat adjustment until the brake stops firmly without locking the wheel.

Product facts

Parts: Rear Brake (complete) for Flex Black - Part #1575: Complete rear brake assembly for Flex Black, part #1575. This is a direct replacement, so you get all necessary brake components in one package.
Parts: Rear Brake (complete) for Flex Black - Part #1575