152fmh Engine Service Manual < 2025-2027 >

is a popular 110cc, 4-stroke, air-cooled horizontal engine widely used in Chinese pit bikes, ATVs, and scooters. Because it is based on the Honda-style "horizontal" design, service procedures are consistent across many brands like TaoTao, Lifan, and SSR. 1. Essential Engine Specifications Displacement: Single-cylinder, 4-stroke, horizontal. Air-cooled via aluminum fins. Oil Capacity: Approximately 0.8 to 0.9 liters (verify with dipstick). Fuel Consumption: Approximately 2L/100km. Maximum Power: ~7 HP (6.9 PS) at 7,500 rpm. 2. Routine Maintenance Schedule

• Remove valve cover.
• Rotate engine to TDC compression stroke (both valves closed).
• Insert feeler gauge between rocker and valve stem/tappet and adjust nuts or shims as required.
• Reinstall cover with new gasket or sealant if necessary.

Typical Specifications (reference values)

• Type: 4-stroke, OHV, air-cooled, single cylinder
• Displacement: ~152 cc
• Bore x Stroke: commonly ~62 mm x 50 mm (verify for your unit)
• Compression ratio: ~8.5:1 to 9.5:1
• Rated output: ~3.5–5.5 hp depending on tuning and RPM
• Rated speed: 3,600–3,600 RPM (standard small engine speed)
• Ignition: magneto, CDI or breaker-point type
• Carburetion: float bowl carburetor with adjustable idle and mixture screws
• Fuel: unleaded gasoline, lead-free recommended; max octane per manufacturer
• Oil capacity: ~0.6–0.9 L (check dipstick level)
• Recommended oil: SAE 10W-30 or 15W-40 depending on ambient temperature; API SJ or later
• Spark plug: NGK B6HS or equivalent; gap ~0.6–0.7 mm (0.024–0.028 in)
• Valvetrain: overhead valves, mechanical tappets (adjustable) or hydraulic (less common)
• Cooling: fan and shroud with cooling fins on cylinder and head

• Change oil (SAE 10W-40, JASO MA2).
• Clean oil strainer (under left cover – 17mm bolt).

Every 500 km (first month):

This is the most overlooked maintenance task. Tight valves will cause hard starting and eventual engine failure. Engine State: Must be stone cold. 152fmh engine service manual

The Cam Chain Tensioner Reset

After removing the cam chain, the automatic tensioner must be manually retracted using a tiny flathead screwdriver. The manual shows the locking tang mechanism. Most DIYers break this plastic tensioner by forcing it. is a popular 110cc, 4-stroke, air-cooled horizontal engine