The best dirt bike master cylinder depends on whether you need a front or rear unit and whether its mounting dimensions match your bike. The WEIYINGSI model is aimed at right-side front brakes on many 50cc–125cc bikes; the Slother unit targets rear brakes on common Chinese 50cc–125cc models. VRWEARE and SOLLON list key handlebar and banjo-bolt dimensions, while the AnXin listing names specific motorcycle model families but provides fewer specifications.
| Product | Best suited for | Key detail to verify |
|---|---|---|
| WEIYINGSI Right Brake Master Cylinder | Front brake replacement on smaller off-road bikes | Oil screw measurements |
| VRWEARE Motorcycle Brake Pump | Right-hand lever setups needing specified dimensions | 12.7mm piston bore |
| Slother Rear Brake Master Cylinder | Rear brake on many Chinese 50cc–125cc bikes | Mounting-hole size |
| AnXin Rear Brake Master Cylinder | Listed SX, SXF, SMR, SXS, and EXC models | Exact fitment and dimensions |
| SOLLON Hydraulic Brake Master Cylinder | Broad range of listed ATV and pit bike engines | Handlebar and banjo-bolt match |
WEIYINGSI Right Brake Master Cylinder
Best for: Riders replacing a right-side front brake master cylinder on a 50cc–125cc pit bike or ATV with a 7/8-inch handlebar. The listed application includes many 50cc, 70cc, 90cc, 110cc, and 125cc kids’ off-road bikes.
The product specifies a 10mm banjo bolt. Its features also describe a heavy-duty pump body and nitrile rubber seals intended to handle pressure and temperature changes. It is a relevant choice when the existing assembly’s layout and measurements match.
Check before buying: The listing specifically advises confirming the old pump’s oil screw measurements. Do not rely on engine size alone to establish fit.
VRWEARE Universal Right-Hand Brake Pump
Best for: Buyers who want listed dimensions for comparing a right-hand master cylinder with their existing controls. The product specifies a 7/8-inch (22mm) handlebar fit, a 12.7mm piston bore, and a 10×1.25mm banjo bolt.
The listing also identifies an M10 rear-view-mirror hole and describes use across dirt pit bikes, ATVs, quads, mopeds, scooters, buggies, and go-karts. Those measurements make this option useful for shoppers who can check their current hardware rather than selecting by vehicle category alone.
Check before buying: “Universal” does not confirm that the lever orientation, hose connection, or mounting arrangement matches every vehicle. Compare the listed dimensions with the original part.
Slother Rear Brake Master Cylinder
Best for: Owners seeking a rear master cylinder for many Chinese 50cc–125cc dirt bikes or ATVs. The listed applications include Taotao, BMS, Roketa, Xpro, Apollo, SSR, Pitster, Piranha, Sunl, and other named makes.
The product specifies a 10mm banjo bolt and says fit depends on the mounting-hole size. Its described material is aluminum, with the listing identifying wear and corrosion resistance as product characteristics. Choose it when the rear-brake layout and mounting points correspond to your original cylinder.
Check before buying: Brand and engine-size lists are not a substitute for measuring the mounting holes and confirming the brake-line connection.
AnXin Rear Brake Master Cylinder
Best for: Buyers checking a rear-cylinder replacement for models in the listing’s SX, SXF, SMR, SXS, and EXC families, across the stated 125–510 range. It is included for shoppers whose bike matches those named model families.
The available product information identifies it as a rear brake master cylinder, but does not provide measurements or detailed fitment notes. That makes this a more model-specific option to investigate rather than a broad universal pick.
Check before buying: Confirm your exact bike year and model, plus mounting and brake-line dimensions, with the seller or product listing. The provided information is not enough to confirm fit on its own.
SOLLON 7/8-Inch Hydraulic Brake Cylinder
Best for: Riders comparing a right-side hydraulic master cylinder for a broad range of listed 50cc–250cc ATVs, quads, mopeds, motorcycles, and pit bikes. The stated fit includes 7/8-inch (22mm) handlebars and a 10×1.25mm banjo bolt.
The listing names applications including TaoTao, Buyang, Coolsport, Jonway, Znen, NST, Kazuma, Sunl, Roketa, and Orion. This breadth may help shoppers narrow options, but the dimensions remain important for confirming a match.
Check before buying: The listing includes multiple vehicle types and engine sizes; verify the original assembly’s side, hose fitting, and handlebar diameter before ordering.
Buying Guide: How to Choose a Dirt Bike Master Cylinder
Do you need a front or rear master cylinder?
Start by identifying the brake circuit. A right-hand handlebar pump is generally a control assembly for the handlebar, while rear master cylinders are separate products intended for rear-brake setups. The product names here distinguish front/right-hand options from rear units. Match the replacement to the part being removed.
Which dimensions should you compare?
Check handlebar diameter, banjo-bolt thread and size, piston bore when specified, and mounting-hole spacing. A listed 7/8-inch handlebar fit or 10×1.25mm banjo bolt is useful only if it agrees with your existing setup. Measure the original part and compare connection orientation and available clearance.
Is engine size enough to confirm fit?
No. Engine displacement and brand lists are useful starting points, not definitive fitment confirmation. Similar 110cc or 125cc bikes can use different brake layouts or fittings. Check the exact model, year, side of the bike, and physical dimensions. When a listing lacks measurements, seek confirmation before purchase.
When should you choose a model-specific option?
Choose a product with a matching model family when your bike is explicitly listed and its dimensions also match. Choose a broadly described option only when you can verify its specifications against the original cylinder. For rear-brake replacements, prioritize mounting points and hose connection over a long list of compatible engine sizes.
Frequently Asked Questions
What does a dirt bike master cylinder do?
A hydraulic brake master cylinder converts lever or pedal input into pressure in the brake-fluid system. The products listed here are replacement components for different front or rear brake arrangements.
What is a 10mm banjo bolt?
It describes a fitting dimension identified by some product listings. Confirm the bolt and thread specification against your existing brake line and cylinder before selecting a replacement.
Can I use any 7/8-inch master cylinder on my dirt bike?
No. Handlebar diameter is only one fitment factor. Also compare brake side, banjo-bolt specification, piston bore if provided, mounting layout, and vehicle fitment.
Should I replace a front cylinder with a rear one?
No. Select a part designed for the brake position and control arrangement you are replacing. The listings distinguish right-hand handlebar units from rear master cylinders.