4107 Stroker Crankshaft Honda TRX250R 1987 1989

Features: Factory assembled and trued to OEM specifications. Drop in replacement crankshaft requires no modification unless noted . CNC machined and dynamically balanced to suit the increased stroke. Add +2.00 mm to +4.00 mm of stroke depending on application. Uses stock piston unless noted. Main bearings not included . Can be matched with Cylinder Works Big Bore cylinders to get significant displacement and horsepower gains. Not re-buildable as the rods are shorter than OEM.. +4.00 mm stroke increase makes 260 cc with standard piston. Connecting rod side clearance is 0.45 mm - 0.75 mm. IMPORTANT: Head chamber area must be machined 2.00 mm deeper to accept longer stroke crank..