Specifications: Stock Number: DLEG0031 Displacement: 30.5 cc (1.861 cu in) Bore: 1.42 in (36 mm) Stroke: 1.18 in (30 mm) Weight: 2.4 lb (1.10 kg) RPM Range: 1,600-8,500 Output: 3.7 hp @ 8,500 rpm Requires: unleaded gasoline, oil, ignition battery & propeller Includes: electronic ignition, muffler, spark plug, gasket, bolts, machined aluminum standoffs, throttle arm extension & manual Suggested Propellers: 18x8, 18x10, 19x8 & 20x8 Suggested Break-in Prop: 18x8 Technical Data: Ignition Battery: 4.8-8.4V NiCd or NiMH, 6.6V LiFe or 7.4V LiPopack (Voltage regulator required with LiPo or LiFe above 8.4v) Compression Ratio: 7.6:1 Gasoline/Oil Mix: 30:1 Replacement Spark Plug: DLEG3526 Weight Breakdown: Engine: 32.1 oz (910 g); Muffler: 2.1 oz (60 g); Ignition: 4.2 oz (120g)