140mm Brake Rotor G Line Centrelock

The 140mm Center Lock Brake Rotor is a milestone for Brompton, as it is a core component of the G Line—the first-ever Brompton series to feature hydraulic disc brakes. Unlike the rim brakes found on the C, P, and T Lines, this system provides consistent, powerful stopping performance even in wet or muddy off-road conditions.

Product Specifications: 140mm G Line Rotor

The rotor is manufactured by TRP (Tektro Racing Products) specifically to meet the high-torque demands of the G Line's 20-inch wheels.

Feature	Specification
Brompton Part Code	Q103705
Diameter	140mm
Mounting Type	Center Lock (Splined interface)
Material	Stainless Steel (High heat dissipation)
Compatibility	G Line (Front & Rear)
Weight	Approx. 112g
Lockring Torque	40 Nm

Detailed Breakdown

1. Center Lock System

The G Line uses the Shimano Center Lock standard rather than the 6-bolt system. This allows for a much faster installation and removal process using a standard cassette tool. It also ensures the rotor remains perfectly centered, which is vital for the tight tolerances of a folding bike's frame.

2. Optimized for 20-inch Wheels

While 140mm might seem small compared to mountain bikes (which often use 180mm+), it is the "sweet spot" for the G Line's 20-inch wheels. Because of the smaller wheel diameter, a 140mm rotor provides mechanical leverage equivalent to a much larger rotor on a full-sized bike. This prevents "on/off" grabby braking and allows for better modulation (fine control).

3. Safety & Performance

The rotor is designed to work with TRP hydraulic calipers. The stainless steel construction features a specific "drill pattern" that helps:

●     Clear debris: Vital for the "Gravel" nature of the G Line.

●     Dissipate heat: Essential when descending hills on a bike that may be carrying heavy luggage on the front carrier block.

Installation & Maintenance Notes

Compatibility Warning: This rotor is NOT compatible with A, C, P, or T Line Bromptons, as those frames lack disc brake mounts and their hubs are not splined for Center Lock.

●     Front vs. Rear: On the standard G Line, the 140mm rotor is used on both wheels.

●     Torque Matters: Always use a torque wrench to tighten the lockring to 40 Nm. Under-tightening can lead to "brake shudder," while over-tightening can damage the hub splines.

●     Cleaning: Never touch the braking surface with bare fingers, as skin oils can cause "brake squeal." Use isopropyl alcohol for cleaning.

Maintenance Visual Check

If you are inspecting your rotor, look for:

●     Coloration: If the rotor looks "burnt" or blue/purple, it has been overheated and may be warped.

●     Thickness: The minimum thickness (usually 1.5mm) is often stamped on the rotor itself. If it’s thinner than this, it needs replacement for safety.

Brompton Malaysia  

📍 Location: P-10-1, Jalan Jalil Utama 2, Bukit Jalil, 57000 Kuala Lumpur, Wilayah Persekutuan Kuala Lumpur

🕒 Opening Hours: Everyday. Our current operating hours are 11.30am to 8pm. 

Please note that these hours may be subject to change in the future based on circumstances such as public holidays, special events, or operational needs. We recommend checking our Instagram or Facebook or contacting us directly for the most up-to-date information before visiting.

📞 Phone Number: +601115987298 (Whatsapp or call)

🌐 Website: https://www.brompton.my/ 

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