Triumph 5/16″-24 x 3-3/4″ Crankcase Stud PN# 21-1823

Maintain the integrity of your classic Triumph engine with this 5/16″-24 x 3-3/4″ UNF Crankcase Bolt (Part Number 21-1823). Manufactured to original Triumph specifications, this high-quality bolt is essential for secure and precise crankcase assembly on a wide range of Triumph 650cc and 750cc twin models from 1971 to 1983. Key Features Exact Fit: 5/16-inch diameter with 24 threads per inch (UNF), 3-3/4 inches in length for correct alignment and clamping force. Durable Construction: Made from robust steel for strength and reliability, ensuring long-lasting engine performance. OEM Replacement: Direct replacement for Triumph part numbers 21-1823 and S1823, suitable for many “oil in frame” Triumph twins. Easy Installation: Hex head design allows for straightforward installation and removal with standard tools. Authentic Restoration: Perfect for engine rebuilds and restorations, retaining the original look and function of your vintage motorcycle. Typical Applications Used as a crankcase bolt on Triumph 650 and 750 twins, including TR6, T120, and T140 models produced from 1971–1983. Ensures proper joining of crankcase halves, critical for engine assembly and reliability. Specifications Part Number 21-1823 Diameter 5/16 inch Thread Type UNF (Unified National Fine) Threads Per Inch 24 TPI Length 3-3/4 inch (95 mm) Application Crankcase bolt (Triumph 650/750 twins, OIF) Choose this genuine Triumph crankcase bolt for dependable engine assembly and a factory-correct restoration on your classic motorcycle. 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.