Royal Enfield 1100683/F – Rear Master Cylinder Assembly (OEM) For Reborn & Bullet 350 J Series

Restore factory braking performance with the Royal Enfield 1100683/F Rear Master Cylinder Assembly—a genuine OEM hydraulic unit for J-Series Classic 350 (2021–on) and J-Series Bullet 350 (2023–on). Built to Royal Enfield specifications, the assembly maintains correct bore size, piston travel and seal integrity for consistent rear-brake pressure and a firm, predictable pedal feel.

Each unit comes pre-configured for a straightforward swap onto the OEM bracket. Replace a leaking or spongy cylinder during routine service or accident repair to bring back reliable, ABS-ready braking response. As an OE part, 1100683/F matches your original fittings and brake line connection, eliminating trial-and-error and ensuring long service life in Indian riding conditions.

Tip: Always bleed the system with fresh DOT brake fluid after installation and inspect pads/rotor while you’re there for best results.

Key features

• Genuine OEM rear master cylinder — RE P/N 1100683/F.

• Direct fit for Classic 350 Reborn (J-Series) and Bullet 350 J-Series—no mods. 

• Factory-matched bore & piston for proper hydraulic ratio and brake feel.

• Leak-resistant OE seals and durable body for long service life.

• ABS compatible when fitted on OE systems; retains stock brake performance.

• Installation friendly: mounts to OE bracket; reuse OE hose/clevis where applicable.

What’s included

• Rear master cylinder assembly with reservoir (as per OEM supply).

FAQs

1) Will 1100683/F fit my Classic 350 Reborn (2021+) exactly?
Yes—this is the OEM rear master cylinder for the J-Series Classic 350 (2021→). 

2) Does it fit the new Bullet 350 (J-Series, 2023→)?
Yes—listed by multiple reputable sellers specifically for Bullet 350 J-Series. 

3) Does it fit Hunter 350 or Meteor 350?
No—don’t assume. Hunter typically uses RAB00874/A; Meteor dealer listings reference 1100728. Match the OE number on your bike before ordering. 

4) Is this a genuine Royal Enfield part?
Yes—1100683/F is shown in the official RE parts catalog.

5) Are hoses or hardware included?
The assembly is supplied as the master cylinder/reservoir. Reuse your OE hose and pedal linkage unless damaged.