140cc 4-Stroke Racing Engine Motor with Electric Start & Manual Clutch – Horizontal Pit Dirt Bike Engine for CRF50, XR50, CT70, Z50, Monkey, SSR125, Taotao, Coolster, Apollo RFZ 125cc YX140 DTE140

Dominate the Track with Our 140cc Racing Engine Upgrade!Transform your pit bike, mini trail, or monkey bike into a track-ready machine with this high-performance 140cc 4-stroke racing engine. Designed for riders who demand explosive acceleration, reliable starting, and race-proven durability, this engine is the perfect upgrade for CRF50, XR50, CT70, Z50, and most horizontal engine pit bikes.⚙️ Technical Specifications:Engine Type: Horizontal, single-cylinder, 4-stroke, air-cooledDisplacement: 140ccStarting System: Electric start + kick start backupTransmission: 4-speed manual (0-1-2-3-4)Sprocket: 15T, 428 chain, 17mm (0.67") shaftBore × Stroke: 56 × 57 mm (2.20" × 2.24")Max Power: 7 kW @ 8500 RPM ±5%Max Torque: 9.5 N·m @ 5500 RPM ±5%Compression Ratio: 8.8:1Mounting Bolt Spacing: 154mm (6.0")Oil Capacity: 900 ml (15W/40-SE recommended)🏁 Performance Features:Electric Start + Kick Backup: Never worry about dead batteries – dual start system ensures you're always ready to ride, whether at the track, on the trail, or in cold weather.Racing-Tuned Power: 140cc displacement with aggressive gear ratios delivers explosive acceleration out of corners and hill-climbing torque when you need it most.Manual Clutch Control: 4-speed transmission with manual clutch gives you precise throttle control for racing, track training, and advanced rider development.Horizontal Cylinder Design: Lower center of gravity improves handling, weight transfer, and cornering stability – essential for competitive riding.High-RPM Durability: Performance-tuned valve train maintains mid-range throttle response while surviving sustained high-RPM operation.🔧 Vehicle Compatibility:Honda: CRF50, CRF70, XR50, XR70, Z50, Z50R, CT70, CT90, CT110, ST70, QA50, QR50, SL70, SL90, CS90, ZB50Aftermarket: Monkey, Minitrail, Clone FramesChinese Brands: SSR110, SSR125, Coolster 125, Taotao DB14, Taotao DB17, Apollo RFZ125Engine Codes: YX140, DTE140, and most horizontal pit bike engines📦 Package Includes:1 × 140cc Racing Engine Motor1 × Kick Starter Lever1 × Gear Shift Lever1 × Intake Manifold Assembly1 × Engine Cover💡 Important Installation Notes:⚠️ Always verify mounting bolt spacing (154mm/6.0"), sprocket alignment, throttle cable routing, and exhaust clearance before purchase⚠️ Some models may require carburetor jetting adjustment, intake port angle modification, or bracket fabrication⚠️ Professional installation by qualified powersports technician recommended for optimal performance⚠️ Use proper break-in procedure and 4-stroke oil rated 15W/40-SE⚠️ Carburetor sold separately – compatible with most 26mm-28mm pit bike carburetors

Dual Start Convenience】 – Features electric start + kick start backup for reliable ignition in cold weather, trail stops, and race conditions. No more dead batteries on the track!

【Racing-Ready 140cc Power】 – 140cc displacement delivers 7kW @ 8500 RPM and 9.5 N·m torque for explosive acceleration and hill-climbing torque. Perfect for racing, track training, and aggressive trail riding.

Precision Manual Clutch】 – 4-speed manual transmission with 0-1-2-3-4 gear pattern provides tighter throttle control for advanced rider development and competitive racing.

【Universal Pit Bike Fitment】 – 154mm (6.0") mounting bolt spacing fits CRF50, CRF70, XR50, XR70, Z50, CT70, CT90, ST70, Monkey, SSR125, Taotao DB14/DB17, Coolster 125, Apollo RFZ125, YX140, DTE140 and most horizontal engine pit bike frames.

【Complete Package】 – Includes engine, kick starter lever, gear shift lever, intake manifold assembly, and engine cover – everything needed for installation (carburetor sold separately).