Mikuni Bs26 Carburetor Manual Verified [2026]
Verified Sources
The information provided in this article has been verified through the following sources:
Conclusion
The Mikuni BS26 carburetor is a reliable and performance-oriented carburetor model. By following the verified guide provided in this article, you can ensure proper adjustment, maintenance, and repair of your Mikuni BS26 carburetor. Remember to consult the official Mikuni carburetor manual and other verified sources for specific information on your carburetor model.
Additional Resources
For more information on the Mikuni BS26 carburetor, you can consult the following resources:
Specifications
Disclaimer
The information provided in this article is for general information purposes only. Consult the official Mikuni carburetor manual and other verified sources for specific information on your carburetor model. The author and publisher disclaim any liability for damages or injuries resulting from the use of the information provided in this article.
Mikuni BS26 Carburetor Manual Verified
The Mikuni BS26 carburetor is a popular and highly-regarded carburetor used on a variety of motorcycles, scooters, and other small engines. Known for its reliability and performance, the BS26 has become a favorite among enthusiasts and mechanics alike. In this article, we'll provide a comprehensive manual for the Mikuni BS26 carburetor, including specifications, troubleshooting tips, and maintenance procedures.
Specifications
Components and Diagram
The Mikuni BS26 carburetor consists of the following components:
Troubleshooting Tips
Maintenance Procedures
Verification and Validation
To verify and validate the information provided in this manual, we have consulted the following sources:
Conclusion
The Mikuni BS26 carburetor is a reliable and high-performance carburetor that requires regular maintenance to achieve optimal performance. By following the specifications, troubleshooting tips, and maintenance procedures outlined in this manual, you should be able to keep your BS26 carburetor running smoothly and efficiently.
Disclaimer
The information provided in this manual is for general information purposes only. Always consult the manufacturer's instructions and specifications for specific details and guidelines. We are not responsible for any damage or injury caused by incorrect use or modification of the Mikuni BS26 carburetor.
The Mikuni BS26 is a 26mm constant velocity (CV) carburetor. It is highly popular in mid-sized motorcycles, ATVs, and scooters like the Suzuki Burgman 125. This guide provides a verified article for servicing, maintaining, and tuning your unit based on standard Mikuni factory manual specifications. 🛠️ Core Carburetor Circuits
To properly tune the Mikuni BS26, you must understand its five overlapping metering systems that manage fuel delivery:
Pilot Circuit: Controls engine idle and initial throttle opening.
Throttle Valve (Slide): Regulates air intake and controls transition to the mid-range.
Needle Jet & Jet Needle: Governs mid-range performance between 1/4 and 3/4 throttle. Main Jet: Dictates fuel flow at wide-open throttle (WOT).
Choke (Starter) Circuit: Supplies a rich mixture for cold engine starts. 🔧 Step-by-Step Tuning Guide mikuni bs26 carburetor manual verified
Before making adjustments, always ensure the engine is fully warmed up and the air filter is clean. Mikuni Bs 26 Manual - MCHIP
Searching for "Mikuni BS26 carburetor manual verified" often returns generic Mikuni tuning books. Those are helpful, but they lack model-specific emissions data.
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 |
On a twin-cylinder BS26 setup, there is no vacuum port for a traditional sync gauge on the left carb (it has a choke only).
With BS26 on parallel twins (e.g., GS500), syncing is mandatory:
Every "verified" manual warns about this: Do not force the PAS. The BS26 uses a fine-tip screw with a tiny O-ring and washer.
The Mikuni BS26 is a round-slide, constant-velocity (CV) carburetor commonly used on small single-cylinder motorcycles and scooters (e.g., 125–250 cc). It combines a vacuum-operated slide with a fixed main jet and pilot system to provide smooth throttle response across the rev range.
The BS26 uses soft aluminum body castings. Over-tightening is the #1 cause of stripped threads. Verified Sources The information provided in this article
| Fastener | Verified Torque (in-lbs) | Warning | | :--- | :--- | :--- | | Float Bowl screws | 7-9 in-lbs | Use a JIS screwdriver, not Phillips. | | Top cap screws (diaphragm cover) | 4-6 in-lbs | Overtightening distorts the diaphragm sealing surface. | | Drain plug (bottom of bowl) | 13 in-lbs | Replace the copper crush washer every time. | | Choke plunger nut | Hand tight + 1/8 turn | Plastic threads—do not use tools. |
