125cc motor engine wiring kit electric start semi-auto for atv go kart atc70 110 brand new 125cc engine semi auto. ENGINE SIZE 125CC GEAR SYSTEM 3 FORWARD NEUTRAL REVERSE Type Horizontal, single-cylinder, 4-stroke, air-cooled Start Method Electrical Start Bore x Stroke 52.4×55.5mm, 119.7mL Compression ratio 9.01 Maximum net power/ rpm 5.8 kw/7500r/min±375 r/min Maximum torque/ rpm 8.5 N.