Triumph 350 & 500 Unit connecting rod insert bearings

Whether you call them rod bearings, insert bearings, shell bearings, or big end bearings, they are a very important part of your engine.

Available in standard and four different undersizes, and supplied in sealed packages of four (for two rods).

Triumph factory part number 70-3706

Triumph 350 and 500 connecting rod journal bore is 1.5630" (+/- .0005") when torqued.

Fits Unit construction 500cc and 350cc connecting rods. These are also the inserts used for pre unit "conversion" rods (like Thunder Engineering and LF Harris), that make it possible to grind a pre unit crank to unit 500 journal specs. 

Please see our tech page for crankshaft journal sizes

 For printable PDF crankshaft journal sizes click here