Restore optimal carburetor performance with the M5L-46-88 motorcycle carburetor diaphragm, a precision aftermarket rubber membrane designed for classic BMW Airhead models equipped with Bing CV 40mm constant-velocity carburetors. As a professional Chinese manufacturer exporting worldwide, we produce this critical component to exacting standards, ensuring reliable fit, long service life and consistent quality for bulk purchasers, motorcycle parts distributors, repair workshops and fleet operators.
Key Specifications:
- Part Number: M5L-46-88
- Inner Diameter: 46 mm
- Outer Diameter: 88 mm
- Material: High-quality fuel-, oil- and heat-resistant rubber
Primary Compatible Models:
- BMW R45, R65, R75, R80, R90, R100 series (various years) fitted with Bing CV 40mm carburetors
- Suitable for a wide range of BMW Airhead / R2V models using matching 46 mm ID / 88 mm OD diaphragms
Product Features & Benefits:
- Direct-fit design matching original equipment dimensions for straightforward installation
- Flexible, durable rubber resistant to gasoline, ethanol blends, oil, heat and aging
- Restores proper vacuum operation of the carburetor slide / throttle valve for improved throttle response, stable idle and smooth engine performance
- Helps resolve common issues caused by cracked, hardened, porous or leaking diaphragms (poor acceleration, uneven running, fuel delivery problems)
- Precision manufactured for consistent thickness, flexibility and sealing performance across production batches
- Cost-effective OEM-compatible alternative ideal for volume buyers
Why Choose Our M5L-46-88 Diaphragm? We specialize in high-volume production of motorcycle carburetor components for the global aftermarket. Every diaphragm undergoes quality checks to meet the demands of professional rebuilders and distributors. Our factory-direct supply supports competitive pricing, flexible order quantities, reliable lead times and stable long-term partnerships for bulk importers and wholesale customers worldwide.
Applications: Perfect for carburetor rebuilds, routine maintenance, restoration projects and high-mileage repair work on classic BMW Airhead motorcycles. Widely used by independent workshops, dealerships and parts retailers specializing in BMW classic models.





