The engine is a six-cylinder
four-stroke,
horizontally-opposed, 3,888 cc (237.3 cu in) displacement, air-cooled, direct-drive, gasoline engine design. It employs dual
electronic ignition and produces 140 to 160 hp (104 to 119 kW) at 3300 rpm.[1]
Variants
UL390i
Base model with fuel injection and a
compression ratio of 8.2:1, producing 140 hp (104 kW) at 3300 rpm[1][2]
UL390iS
Model with fuel injection and a 9.1:1 compression ratio, producing 160 hp (119 kW) at 3300 rpm[3]
UL390iA
Inverted oil system version of the UL390iS, producing 160 hp (119 kW) at 3300 rpm[4]