Mikuni Bs26 Carburetor Manual Verified May 2026
You searched for "Mikuni BS26 carburetor manual verified" to buy parts, didn't you? Beware.
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 |
The Mikuni BS26 is not a bad carburetor; it is a precise instrument that was calibrated in the 1980s for a specific intake tract. The frustration comes from using unverified data from anonymous forum posters.
By using the verified manual specs outlined in this article—float height of 13.0mm, pilot screw at 2.5 turns, legitimate OEM diaphragms, and a stock air box—your BS26 will start on the first choke pull in freezing weather and idle like a sewing machine.
Download the manual. Verify the part numbers. And never trust a generic YouTube comment again.
Need a specific torque value or jet size for your exact year and model? Leave a comment below with your bike’s VIN prefix, and we will pull the verified page from the factory manual. mikuni bs26 carburetor manual verified
The Mikuni BS26 is a Constant Velocity (CV) carburetor commonly found on small-displacement motorcycles like the Suzuki GS125, GN125, and Burgman 125/150. Verified manual data emphasizes that the carburetor operates through five overlapping metering systems—pilot, throttle valve, needle jet/needle, main jet, and choke—which primarily regulate performance between 1,750 and 4,500 RPM. Core Specifications & Tuning Data
Based on verified service documentation, here are the standard parameters for the BS26 series: Bore Size: 26mm. Idle Speed: Typically 1,450–1,550 RPM.
Float Height: Standard is 17mm (though this can vary by specific model application).
Pilot Screw: Starting point is generally 1.5 to 2 turns out from lightly seated. Service & Maintenance Guide
Verification of Authenticity: Genuine Mikuni carburetors have "Mikuni Corp" cast into the slide side and "Made in Japan" cast above the float bowl seam. Avoid substitutes, as non-genuine jets often lack precise calibration.
Cleaning Essentials: Use a dip basket or specialized cleaner for stubborn varnish, but always remove rubber gaskets and O-rings first to prevent swelling. Blow out all orifices with compressed air after soaking. You searched for "Mikuni BS26 carburetor manual verified"
Rebuild Tools: Use JIS (Japanese Industrial Standard) Phillips screwdrivers to avoid stripping the soft brass or aluminum screws common on these units. Step-by-Step Tuning Order
For optimal performance, Mikuni recommends following this specific sequence: How to spot a counterfeit Mikuni carburetor
Mikuni BS26 Carburetor Manual: A Verified Guide
The Mikuni BS26 carburetor is a popular and widely used carburetor model in the automotive and motorcycle industries. Known for its reliability and performance, the BS26 carburetor has been a staple in many vehicles for decades. However, like any complex device, it requires proper maintenance, adjustment, and repair to function optimally. In this article, we will provide a comprehensive guide to the Mikuni BS26 carburetor manual, verified through various sources to ensure accuracy and reliability.
Introduction to the Mikuni BS26 Carburetor
The Mikuni BS26 carburetor is a vacuum-piston carburetor designed to provide a precise air-fuel mixture to the engine. It features a simple and rugged design, making it easy to maintain and repair. The BS26 carburetor is commonly used in motorcycles, scooters, and ATVs, but it can also be found in other applications such as go-karts and mini-bikes. These settings are for a stock, unmodified engine
Components of the Mikuni BS26 Carburetor
Before diving into the manual, it's essential to understand the components of the Mikuni BS26 carburetor. The main components include:
Mikuni BS26 Carburetor Manual
The following is a verified guide to adjusting, maintaining, and repairing the Mikuni BS26 carburetor:
Many online guides incorrectly suggest inverting the carburetor fully. The factory manual specifies a 30° angle (float tang just touching the needle spring tip, not compressing it). Full inversion compresses the spring and gives a false reading (~11 mm vs correct 13 mm), causing a lean condition.