This Triumph 650 Flywheel Bolt 70-3907 is an important part of the crankshaft assembly, as it not only secures the flywheel to the crankshaft, but also locates the sludge trap. This bolt is specific to the Triumph 650 crankshafts with the full-width flywheel, as specified for the 1960-1965 and 1969-1970 models. Not compatible with narrow lightened flywheels from the 1966-1968 and 1971-1972 model years.
The hardened steel flywheel bolt is threaded to 3/8″-26 TPI and features a special tip on the end for locating the alignment hole on the crankshaft oil tube, or “sludge trap”. Suitable for fitment on the full-width flywheels from 1960-1970.
There are (3) flywheel bolts securing the flywheel to the crankshaft, all originally recommended to be treated with D524 Loctite thread sealant. It is imperative to have the correct torque specification observed when fitting a flywheel bolt. The oil tube must be fully inserted in place to allow the flywheel bolt to lock it into place.
Removal of the flywheel bolt requires heat to be applied to the vicinity of the crankshaft web where the bolt is threaded in. High-strength thread-locking compound needs to be warmed to allow it to release the bolt when backed out of the crankshaft. Red Loctite is recommended to be applied to the clean threads of the bolt when installing. The recommended torque specification for the flywheels bolts is 33 ft. lbs.
Key Features of Triumph 650 Flywheel Bolt 70-3907:
- Precision Engineering: Manufactured to the original specifications, ensuring a perfect fit and optimal performance for your Triumph 650.
- High-Quality Materials: Made from durable, high-strength steel to withstand the rigors of engine operation and provide long-lasting reliability.
- Authentic Replacement: Ideal for restoration projects, this bolt maintains the authenticity of your vintage motorcycle, preserving its historical value.
- Compatibility: Designed specifically for Triumph 650 models from the years 1960-1965 and 1969-1970, ensuring seamless integration with your bike’s existing components.
- Ease of Installation: Engineered for straightforward installation, allowing you to replace your old or worn-out flywheel bolt with minimal hassle.
Applications:
- Triumph 650 Motorcycles: Compatible with a range of Triumph 650 models, including the Bonneville and Tiger, from the specified years.
- Restoration Projects: Perfect for enthusiasts and restorers aiming to bring their classic Triumph motorcycles back to their original glory.
Additional Items to Consider:Â
- Triumph Pre-Unit and Unit 650 750 BSA 500 650 Twins Sludge Trap Tube PN# 70-3903 E3903 68-0185
- Triumph 650 Hex Sludge Tube Plug CEI Hepolite PN# 70-3905 H
- Triumph 650 750 Hex Sludge Trap Plug 1972-1985 PN# 71-2800 H
- Triumph 650 750 Bonneville Tiger Trophy Sludge Trap Tap 7/8″ X 20 TPI PN# TBS-0606
LF Harris motorcycle spares are produced to the highest quality standards possible utilizing original Triumph tooling, dies, factory blueprints & materials combined with modern manufacturing equipment, tolerances & techniques.