Upgrade or restore your classic Triumph motorcycle with this high-quality 5/16″-18 x 1-3/4″ Hex Head Crankcase Bolt (Part Number 14-6220). Engineered to meet original equipment specifications, this bolt is designed for secure and reliable engine assembly, ensuring the integrity of your crankcase.
Key Features
- Precision Fit: 5/16-inch diameter with 18 threads per inch (UNC), matching original Triumph specifications for a perfect fit.
- Durable Construction: Manufactured from robust materials for long-lasting performance and resistance to corrosion.
- Partially Threaded: Provides optimal clamping force and alignment, as required for crankcase assembly.
- Hex Head Design: Allows for easy installation and removal with standard tools.
- OEM Replacement: Direct replacement for Triumph part number 14-6220, compatible with a range of classic Triumph and BSA models.
Typical Applications
- Crankcase clamping bolt for Triumph unit twins and triples (including T120 Bonneville, T140, TR6, TR7) from 1968 onward.
- Used in engine bolt sets for 650cc Triumph engines (1969–1970).
- Suitable for various classic British motorcycles requiring this specification.
Specifications
- Part Number 14-6220
- Diameter 5/16 inch
- Thread Type UNC (Unified National Coarse)
- Threads Per Inch 18 TPI
- Length 1-3/4 inch (44 mm)
- Head Type Hex head
- Threading Partially threaded
Restore your vintage motorcycle with confidence—choose this authentic Triumph crankcase bolt for reliable performance and a factory-correct finish.
The product images shown are for illustrative purposes only and may not be an exact representation of the product received. Manufacturers occasionally make minor cosmetic changes to items, such as color, finish, label, or design. These changes do not impact the item’s function or compatibility. Please contact us if you have specific concerns regarding appearance.





