BANSHEE 4MM STROKER CRANK 58MM STROKE--POLISHED RODS WITH KEYED CENTER SHAFT NOT JUST PINNED TO PREVENT CRANK TWISTING OUT OF PHASE UNDER HEAVY USAGE AND RACING CONDITIONS-ALSO SPEEDS UP REBUILDING.NO MACHINING TO CASE NEEDED WITH THIS CRANK.INCLUDES STROKER PLATE & GASKETS FOR BASE- UPPER NEEDLE BEARINGS AND CRANKSEALS-- IF EXHAUST IS LESS THAN 28 MM USE SP4MM PLATE. YOU CAN USE ANY STOCK PIN HEIGHT BANSHEE PISTON WITH THIS CRANK.