120AX

Perfect for 3D, precision and sport flying!

It's a fantastic way to ratchet up horsepower for more flying fun! The 120AX, which boasts 20% more displacement than a .91, can turn bigger props with ease, resulting in improved 3D, precision and sport flying. Boost your plane's performance, without compromising weight — bolt in a 120AX and see the difference for yourself!

O.S. 2-year Limited Warranty


With the 120AX and .91 side by side, you can see how they're virtually identical in size — but you'll enjoy a big difference in performance!

With the 120AX, there's no need to buy an expensive aftermarket muffler! The included Power Box™ muffler comes with two adapters — one of which turns the muffler 90° to become a "Pitts style."
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Stock Numbers:
    OSMG0650 - with muffler
    OSMG0651 - without muffler
Displacement: 1.20 cu in (20 cc)
Bore: 1.197 in (30.4 mm)
Stroke: 1.083 in (27.5 mm)
Practical rpm: 1,800-9,500
Output: 3.1 hp @ 9,000 rpm
Engine weight: 22.8 oz (647 g)
Muffler weight:
    7.07 oz (219 g) with 90° adapter installed
    7.91 oz (245 g) with extension installed
Includes: #8 glow plug, 70D dual-needle carburetor, E-5020 Power Box muffler w/two adapters
Recommended Props: 15x10-12, 16x8-10

Primary Accessories

Stock Number Mfr Number Product Description Quantity Needed
 GPMQ4131   GPMQ4131  Great Planes Silicone Fuel Tubing Standard 3' 1
 GPMQ4150   GPMQ4150  Great Planes Ultra Precision Fuel Filter 1
 TOPQ5205   TOPQ5205  Top Flite 16x8 Power Point Propeller 1

Field Equipment

Stock Number Mfr Number Product Description Quantity Needed
 GPMP2012   GPMP2012  Great Planes Standard ProGlo Starter w/Charger 1
 HCAP2550   HCAP2550  Hobbico 4-Way Wrench w/Plug Storage 1
 HCAP3015   HCAP3015  Hobbico Hand-Crank Fuel Pump 1

Optional Accessories

Stock Number Mfr Number Product Description Quantity Needed
 DTXR0185   DTXR0185  Duratrax Engine Tuning Screwdriver 1
 DTXR0187   DTXR0187  Duratrax Engine Tuning Tool 1
 HCAP3105   HCAP3105  Hobbico Top Fueler MkIII 1
 HCAP3107   HCAP3107  Hobbico Top Fueler MkIII Panel Ready 1
 HCAP3300   HCAP3300  Hobbico TorqMaster 180 Heavy Duty 12 Volt 1
 HCAP3305   HCAP3305  Hobbico Panel Ready TorqMaster 180 1
 HCAR0625   HCAR0625  Hobbico Long Nose Pliers 6" 1
 OSMG2693   71605100  O.S. #10 A5 Glow Plug Cold Air 1