Verified: Mikuni Bs26 Carburetor Manual

These settings are for a stock, unmodified engine at sea level.

| Component | Specification | Notes | | :--- | :--- | :--- | | Identification Mark | BS26 | Stamped on the body | | Bore Size | 26mm | | | Pilot Jet (Slow Jet) | #35 or #40 | Varies by model year/market | | Main Jet | #110 - #125 | Varies by model (Check specific model manual) | | Jet Needle | 4F17 or 4D01 | Clip position usually 3rd groove from top | | Pilot Screw (Air Screw) | 1-3/4 turns out | Factory Preset; Usually capped | | Float Height | 22.4mm ± 1.0mm | Measured from gasket surface to float tang (float hanging down, just touching needle) | | Idle Speed | 1400 ± 100 RPM | | | Throttle Cable Play | 2–4mm | Free play at the throttle grip | mikuni bs26 carburetor manual verified


You have cleaned the carb. You have the kit. But 90% of BS26 failures come from improper reassembly. Here is the verified workflow. These settings are for a stock, unmodified engine

Before reinstalling on the bike:


Myth 1: “The BS26 main jet can be changed without removing the carburetor.” You have cleaned the carb

Myth 2: “The pilot screw controls fuel, not air.”

Myth 3: “You need to drill out a plug to adjust the pilot screw.”