{"product_id":"ums-5-cylinder-75cc-petrol-radial-engine-4-stroke-scale-aircraft-powerplant","title":"UMS 5-Cylinder 75cc Petrol Radial Engine – 4-Stroke Scale Aircraft Powerplant","description":"\u003cp data-start=\"301\" data-end=\"623\"\u003eThe \u003cstrong data-start=\"305\" data-end=\"349\"\u003eUMS 5-Cylinder 75cc Petrol Radial Engine\u003c\/strong\u003e delivers authentic radial sound, realistic scale appearance, and smooth 4-stroke performance in a compact, lightweight package. Supplied ready to run, it is the ideal powerplant for smaller scale warbirds and vintage aircraft requiring dependable petrol radial performance.\u003c\/p\u003e\n\u003ch2 data-start=\"630\" data-end=\"658\"\u003e\u003cstrong data-start=\"633\" data-end=\"656\"\u003eProduct Description\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cp data-start=\"660\" data-end=\"966\"\u003eThe \u003cstrong data-start=\"664\" data-end=\"701\"\u003eUMS 5-Cylinder 75cc Radial Engine\u003c\/strong\u003e combines classic radial realism with modern precision engineering. Designed specifically for scale aircraft builders, this 4-stroke petrol engine offers the distinctive sound, appearance, and smooth power delivery associated with full-size radial aircraft engines.\u003c\/p\u003e\n\u003cp data-start=\"968\" data-end=\"1329\"\u003eWith a \u003cstrong data-start=\"975\" data-end=\"996\"\u003e75cc displacement\u003c\/strong\u003e, this engine is perfectly suited to smaller scale warbirds, vintage models, and detailed replica builds where weight, balance, and authenticity matter. Delivered \u003cstrong data-start=\"1159\" data-end=\"1175\"\u003eready to run\u003c\/strong\u003e, it includes an exhaust collector ring, spark plugs, electronic ignition system, and engine mount for straightforward installation and reliable starting.\u003c\/p\u003e\n\u003cp data-start=\"1331\" data-end=\"1626\"\u003eAll major components are \u003cstrong data-start=\"1356\" data-end=\"1410\"\u003eprecision CNC-machined from aluminium or bar stock\u003c\/strong\u003e, ensuring consistent manufacturing tolerances and dependable performance. The \u003cstrong data-start=\"1489\" data-end=\"1543\"\u003eaircraft-grade alloy cylinder heads and crankcases\u003c\/strong\u003e provide excellent strength-to-weight ratio and thermal stability during operation.\u003c\/p\u003e\n\u003cp data-start=\"1628\" data-end=\"1996\"\u003eA \u003cstrong data-start=\"1630\" data-end=\"1670\"\u003eheavy-duty double-bearing crankshaft\u003c\/strong\u003e ensures smooth, vibration-controlled performance and long service life. Internally, billet aluminium pistons fitted with hardened steel rings operate within \u003cstrong data-start=\"1828\" data-end=\"1870\"\u003ehard-chromed and lapped cylinder bores\u003c\/strong\u003e, reducing friction and enhancing durability. Hardened steel camshafts provide precise valve timing and long-term reliability.\u003c\/p\u003e\n\u003cp data-start=\"1998\" data-end=\"2224\"\u003eDesigned to operate on \u003cstrong data-start=\"2021\" data-end=\"2045\"\u003e87–110 octane petrol\u003c\/strong\u003e with a \u003cstrong data-start=\"2053\" data-end=\"2081\"\u003e32:1 fuel-to-oil mixture\u003c\/strong\u003e, this compact radial engine offers flexibility, efficiency, and dependable power for scale aviation enthusiasts seeking true radial character.\u003c\/p\u003e\n\u003ch2 data-start=\"2231\" data-end=\"2252\"\u003e\u003cstrong data-start=\"2234\" data-end=\"2250\"\u003eKey Features\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cul data-start=\"2254\" data-end=\"2917\"\u003e\n\u003cli data-start=\"2254\" data-end=\"2323\"\u003e\n\u003cp data-start=\"2256\" data-end=\"2323\"\u003e5-cylinder 4-stroke radial engine with authentic scale appearance\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2324\" data-end=\"2378\"\u003e\n\u003cp data-start=\"2326\" data-end=\"2378\"\u003e75cc displacement ideal for smaller scale aircraft\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2379\" data-end=\"2456\"\u003e\n\u003cp data-start=\"2381\" data-end=\"2456\"\u003eSupplied ready to run with ignition, plugs, collector ring \u0026amp; engine mount\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2457\" data-end=\"2520\"\u003e\n\u003cp data-start=\"2459\" data-end=\"2520\"\u003ePrecision CNC-machined aluminium and bar stock construction\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2521\" data-end=\"2575\"\u003e\n\u003cp data-start=\"2523\" data-end=\"2575\"\u003eAircraft-grade alloy cylinder heads and crankcases\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2576\" data-end=\"2637\"\u003e\n\u003cp data-start=\"2578\" data-end=\"2637\"\u003eHeavy-duty double-bearing crankshaft for smooth operation\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2638\" data-end=\"2692\"\u003e\n\u003cp data-start=\"2640\" data-end=\"2692\"\u003eBillet aluminium pistons with hardened steel rings\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2693\" data-end=\"2750\"\u003e\n\u003cp data-start=\"2695\" data-end=\"2750\"\u003eHard-chromed and lapped cylinder bores for durability\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2751\" data-end=\"2805\"\u003e\n\u003cp data-start=\"2753\" data-end=\"2805\"\u003eHardened steel camshafts for reliable valve timing\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2806\" data-end=\"2865\"\u003e\n\u003cp data-start=\"2808\" data-end=\"2865\"\u003eIntegrated choke and throttle bellcranks for easy setup\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2866\" data-end=\"2917\"\u003e\n\u003cp data-start=\"2868\" data-end=\"2917\"\u003eCompatible with 87–110 octane petrol (32:1 mix)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 data-start=\"2924\" data-end=\"2944\"\u003e\u003cstrong data-start=\"2927\" data-end=\"2942\"\u003ePerfect For\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cul data-start=\"2946\" data-end=\"3149\"\u003e\n\u003cli data-start=\"2946\" data-end=\"2975\"\u003e\n\u003cp data-start=\"2948\" data-end=\"2975\"\u003eSmaller scale RC warbirds\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2976\" data-end=\"3015\"\u003e\n\u003cp data-start=\"2978\" data-end=\"3015\"\u003eVintage and classic aircraft builds\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"3016\" data-end=\"3058\"\u003e\n\u003cp data-start=\"3018\" data-end=\"3058\"\u003eLightweight radial engine applications\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"3059\" data-end=\"3102\"\u003e\n\u003cp data-start=\"3061\" data-end=\"3102\"\u003eBuilders seeking realistic radial sound\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"3103\" data-end=\"3149\"\u003e\n\u003cp data-start=\"3105\" data-end=\"3149\"\u003eAdvanced hobbyists and precision modellers\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 data-start=\"3156\" data-end=\"3179\"\u003e\u003cstrong data-start=\"3159\" data-end=\"3177\"\u003eSpecifications\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cp data-start=\"3181\" data-end=\"3514\"\u003e\u003cstrong data-start=\"3181\" data-end=\"3197\"\u003eEngine Type:\u003c\/strong\u003e 4-Stroke\u003cbr data-start=\"3206\" data-end=\"3209\"\u003e\u003cstrong data-start=\"3209\" data-end=\"3223\"\u003eCylinders:\u003c\/strong\u003e 5 (ABC Type)\u003cbr data-start=\"3236\" data-end=\"3239\"\u003e\u003cstrong data-start=\"3239\" data-end=\"3256\"\u003eDisplacement:\u003c\/strong\u003e 75cc\u003cbr data-start=\"3261\" data-end=\"3264\"\u003e\u003cstrong data-start=\"3264\" data-end=\"3273\"\u003eBore:\u003c\/strong\u003e 26.5mm\u003cbr data-start=\"3280\" data-end=\"3283\"\u003e\u003cstrong data-start=\"3283\" data-end=\"3294\"\u003eStroke:\u003c\/strong\u003e 27.5mm\u003cbr data-start=\"3301\" data-end=\"3304\"\u003e\u003cstrong data-start=\"3304\" data-end=\"3323\"\u003eApprox. Thrust:\u003c\/strong\u003e 9kgf @ 24×8 prop\u003cbr data-start=\"3340\" data-end=\"3343\"\u003e\u003cstrong data-start=\"3343\" data-end=\"3357\"\u003eRPM Range:\u003c\/strong\u003e 1,000 – 6,000\u003cbr data-start=\"3371\" data-end=\"3374\"\u003e\u003cstrong data-start=\"3374\" data-end=\"3412\"\u003eWeight (with silencer \u0026amp; ignition):\u003c\/strong\u003e Approx. 3.0kg\u003cbr data-start=\"3426\" data-end=\"3429\"\u003e\u003cstrong data-start=\"3429\" data-end=\"3449\"\u003eEngine Diameter:\u003c\/strong\u003e 230mm\u003cbr data-start=\"3455\" data-end=\"3458\"\u003e\u003cstrong data-start=\"3458\" data-end=\"3476\"\u003eEngine Length:\u003c\/strong\u003e 162mm\u003cbr data-start=\"3482\" data-end=\"3485\"\u003e\u003cstrong data-start=\"3485\" data-end=\"3512\"\u003eRecommended Propellers:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"3515\" data-end=\"3685\"\u003e\n\u003cli data-start=\"3515\" data-end=\"3531\"\u003e\n\u003cp data-start=\"3517\" data-end=\"3531\"\u003e2-Blade 24×8\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"3532\" data-end=\"3685\"\u003e\n\u003cp data-start=\"3534\" data-end=\"3685\"\u003e2-Blade 24×10\u003cbr data-start=\"3547\" data-end=\"3550\"\u003e\u003cstrong data-start=\"3550\" data-end=\"3567\"\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-start=\"3534\" data-end=\"3685\"\u003e\u003cstrong data-start=\"3550\" data-end=\"3567\"\u003eMuffler Type:\u003c\/strong\u003e Collector Ring\u003cbr data-start=\"3582\" data-end=\"3585\"\u003e\u003cstrong data-start=\"3585\" data-end=\"3600\"\u003eSpark Plug:\u003c\/strong\u003e 1\/4-32\u003cbr data-start=\"3607\" data-end=\"3610\"\u003e\u003cstrong data-start=\"3610\" data-end=\"3626\"\u003eCarburettor:\u003c\/strong\u003e Walbro\u003cbr data-start=\"3633\" data-end=\"3636\"\u003e\u003cstrong data-start=\"3636\" data-end=\"3650\"\u003eFuel Type:\u003c\/strong\u003e Petrol (87–110 octane, 32:1 mix)\u003c\/p\u003e\n\u003ch3 data-end=\"3529\" data-start=\"3491\"\u003e\u003cstrong data-end=\"3529\" data-start=\"3495\"\u003eWhy Buy from Probuild Aircraft\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp data-end=\"3723\" data-start=\"3530\"\u003e✅ Official UK stockist – 100% genuine UMS engines\u003cbr data-end=\"3582\" data-start=\"3579\"\u003e✅ Trusted by top international pilots and builders\u003cbr data-end=\"3635\" data-start=\"3632\"\u003e✅ Fast UK shipping and secure packaging\u003cbr data-end=\"3677\" data-start=\"3674\"\u003e✅ Supplying and supporting pilots since 1993\u003c\/p\u003e\n\u003cp data-end=\"3723\" data-start=\"3530\"\u003eManual:\u003c\/p\u003e\n\u003cp data-end=\"3723\" data-start=\"3530\"\u003e\u003ca rel=\"noopener\" href=\"https:\/\/ch-ignitions.com\/wp-content\/uploads\/2020\/03\/ums-gas-radial-engine-manual-9-115.pdf\" target=\"_blank\"\u003e\u003cimg height=\"351\" width=\"233\" alt=\"\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0934\/7711\/0146\/files\/Screenshot_2026-02-04_115553.png?v=1770206937\"\u003e\u003c\/a\u003e\u003c\/p\u003e","brand":"UMS Engines","offers":[{"title":"Default Title","offer_id":56341520023938,"sku":"UMS5-75","price":1850.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0934\/7711\/0146\/files\/UMS-5-75CC-PETROL.jpg?v=1770805263","url":"https:\/\/www.probuild-uk.co.uk\/products\/ums-5-cylinder-75cc-petrol-radial-engine-4-stroke-scale-aircraft-powerplant","provider":"Probuild Aircraft Ltd","version":"1.0","type":"link"}