21 Rear Crank 14mm 7Port Gold Heat Sink Code R217P-P320SG Maximum power 2.70 hp R.P.M 37.000 rpm Practical Range 6.000/44.000 rpm Bore/Stroke 16.26mm/16.80mm Ports 7 Crankshaft 14mm SG Glow Plug Type Standard Exhaust Type Rear