HIAORS Rear Brake Assembly for 50–125cc Pit & Dirt Bikes — 15mm Axle, Master Cylinder + Caliper Kit with Pads

HIAORS rear brake assembly combines a master hydraulic cylinder, caliper and a pair of replacement disc pads designed to restore stopping power on compatible 50cc–125cc pit and dirt bikes.

This complete rear brake unit is a direct-replacement-style component engineered for a range of small-displacement off-road motorcycles and pit bikes. It arrives as a finished assembly — including the master cylinder, caliper and two brake pads — so you can swap it in with minimal fabrication. The listing covers popular models such as SSR, CRF-style, TTR and similar 50–125cc machines, but it is not compatible with SSR 150 models. Confirm axle and mounting dimensions before ordering to ensure a correct fit.

Will this kit fit my pit bike?

Compatibility depends on frame mounts, axle diameter and rotor spacing. This assembly is made for many 50cc–125cc pit and dirt bikes (SSR 125cc, 110cc, CRF/TTR-style models and similar). It is explicitly not for SSR 150 models.

• Fits: SSR 125cc, SSR 110cc, KLX-style, BBR, CRF-style, TTR-style, SDG 107, and many 50cc–125cc bikes
• Not for SSR 150 — do not assume interchangeability
• Includes: 1 brake assembly (master cylinder + caliper) and 1 pair of replacement disc pads
• Verify: 15mm axle and mounting hole alignment before purchase

How do I install the HIAORS rear brake assembly?

Installation is straightforward for anyone comfortable with basic motorcycle maintenance: remove the old rear brake components, align the new assembly to the swingarm mounts and secure with the correct fasteners. Bleed the system after connecting the brake line to eliminate air and ensure consistent pedal feel.

• Tools needed: basic hand tools, torque wrench, brake fluid and bleed kit
• Steps: remove old unit, fit new assembly, connect hose, bleed the brakes
• Tip: double-check axle clearance and pad-to-rotor alignment before final torque

What are the main features and specifications?

This unit pairs a hydraulic master cylinder with a matching caliper and a set of brake pads sized for common small-bike rotors. It’s packaged as a single replacement kit so you receive everything required to restore rear braking components that have worn or failed.

• Package contents: 1x rear brake assembly (master cylinder + caliper) and 1 pair of brake pads
• Designed for 50cc–125cc off-road/pit bikes; check compatibility list above
• Axle reference: 15mm wheel axle compatibility — confirm yours matches
• Not compatible with SSR 150 models

How should I maintain this brake assembly for reliable service?

Basic upkeep keeps braking consistent: inspect pads and rotor for wear, replace fluid periodically, and keep mounting hardware tight. Regular checks after initial installation are important to catch any settling or hose routing issues before they affect performance.

• Inspect pads and rotor thickness every few rides or after heavy use
• Replace brake fluid per manufacturer guidance or if it appears dirty
• Check for leaks, secure fittings and correct hose routing after installation

Who is this for: This HIAORS rear brake assembly is intended for riders, mechanics and hobbyists who need a ready-to-install replacement for the rear braking system on compatible small-displacement dirt and pit bikes. If you own a compatible SSR 110/125, CRF/TTR-style, KLX-style or similar 50–125cc model and you’ve confirmed axle and mount dimensions, this kit supplies the master cylinder, caliper and pads in one convenient package. If you’re unsure about fitment, consult a mechanic or measure your bike’s mounting points before ordering.