Yamaha MX775V-EFI

Yamaha MX775V-EFIThe Yamaha MX775V-EFI is a small (824 cc, 50.3 cu-in) V-twin air-cooled four-stroke internal combustion gasoline engine with vertical shaft, manufactured by Yamaha.

The Yamaha MX775V-EFI motor has two-cylinder, overhead valves and a ball bearing supported P.T.O. The engine is equipped with an industry-standard air filtration system; electronic fuel injected system (Delphi Multec-EFI); ECU controlled electronic ignition coils and an electric starter.

The cylinder bore and the piston stroke is 80.0 mm (3.15 in) and 82.0 mm (3.23 in), respectively. The compression ratio rating is 9.1:1. The MX775V-EFI produces 29.6 PS (22.1 kW) at 3,600 rpm of maximum gross power or 29.0 HP (21.6 kW) at 3,600 rpm of gross rated power (SAE J1995) and 67.9 N·m (6.92 kg·m, 50.1 ft·lb) at 3,100 rpm of torque.

General information

Engine Specifications
Model MX775V-EFI
Type 4-stroke, OHV, V-twin
Displacement 824 cm 3 (50.3 cu-in)
Max. horsepower 29.6 PS (22.1 kW) at 3,600 rpm
Max. torque (crank PTO) 67.9 N·m (6.92 kg·m, 50.1 ft·lb) at 3,100 rpm
Carburetor Delphi Multec – EFI
Cooling system Forced-air
Ignition system ECU Controlled Electronic Ignition Coils
Lubricating system Full pressure with filter
Starting system Electric starter
Stoping system Misfire
Fuel used Unleaded gasoline (octane number 86 or higher)
Fuel tank capacity
Fuel consumption
PTO shaft rotation Counterclockwise (from PTO shaft side)

Service Information

Maximum speed 3550-3600 rpm
Cylinder compression 13.4-14.8 kg/cm2 (190-210 psi)
Valve clearance
Intake valve 0.07-0.13 mm (0.003-0.005 in)
Exhaust valve 0.07-0.13 mm (0.003-0.005 in)
Oil system
Oil type Yamalube 4-stroke or an equivalent (SE or higher)
Recommended oil SAE 10W-30
Oil capacity 2.0 L (2.11 US qt, 1.76 Imp.qt)
Ignition system
Ignition timing BTDC 30° / 3750 rpm
Spark plug NGK: BPR6ES
Spark plug gap 0.7-0.8 mm (0.028-0.031 in)
Spark plug tightening torque 20 N·m (2.0 kg·m, 14 ft·lb)

Valve clearance adjustment data

Calculate the thickness of new adjusting pad so valve clearance comes within specified values.

R = Thickness of removed adjusting pad
N = Thickness of new adjusting pad
M = Measured valve clearance

N = R + [M – 0.13 mm (0.005 in)]

Adjusting pads are available from 1.80 mm (0.0708 in) to 3.00 mm (0.1181 in), in steps of 0.05 mm (0.002 in).

R = 1.80 mm
M = 0.22 mm
N = 1.80 + (0.22 – 0.13) = 1.89 mm, round to 1.90 mm, so we need a adjusting pad with code 190.

Adjust valve celarance at 1000 hr periodic maintenance, normal operational range between periodic maintenance may be 0.02-0.2 mm (0.0008-0.01 in)

Tightening torque
Rocker arm shaft bolt 4.0 Nm (0.40 kg·m, 2.9 lb·ft)
Cylinder head cover bolt 11.0 N·m (1.1 kg·m, 8.0 lb·ft)
ATTENTION! Dear visitors, this site is not a trading platform, an official dealer or a spare parts supplier, so we do not have any price lists or spare parts catalogs. We are an information portal and provide the technical specifications of gasoline and diesel engines.

We try to use verified sources and official documentation, however, differences between sources or errors in entering information may occur. We do not provide advice on technical issues related to the engines operation or repair. We do not recommend using provided information for engines repairing engines or spare parts ordering, use only official service manuals and spare-parts catalogs.

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