Benelli TNT125 Service Manual

 High-voltage package fault;
 Engine control unit (ECU) fails;
 Camshaft position sensor fault;
 Gear switch, starting lock switch or single switch
fault;
 Crankshaft sensor fault;
 Short circuit of main switch or engine flameout
switch;
 Short circuit or open circuit of starting system;
 Main fuse or main switch fuse blows out.
There is problem with fuel / air mixture:
 Bypass screw and / or idling adjustment screw is
abnormal;
 Airway is blocked;
 Air filter is blocked, sealing is poor or missing;
 Oil filling port cover, crankcase ventilation pipe or
air filter drain pipe leaks;
Cylinder pressure is too low:
 Spark plug is loosened;
 Cylinder head is not tight;
 Cylinder and piston is worn;
 Piston rings are damaged (worn, weak, damaged
or stuck);
 The gap between the piston ring and the piston
ring groove is too large;
 Cylinder head gasket is damaged;
 Cylinder head is deformed;
 Valve spring is damage or the elasticity is poor;
 There is no valve clearance;
 Valve is not installed properly (valve is bent or
worn or there is carbon deposition at valve seat).
The running is abnormal during low-speed driving:
Spark is weak:
 Battery voltage is low;
 Anti-theft control system fault;
 High-voltage package fault;
 Short circuit or poor contact of high voltage
package;
 Spark plug is dirty, damaged or clearance is
abnormal;
 Spark plug is not applicable;
 Engine control unit (ECU) fails;
 Camshaft position sensor fault;
 Crankshaft sensor fault.
There is problem with fuel / air mixture:
 Bypass screw is abnormal;
 Airway is blocked;
 Exhaust pipe and exhaust vent is blocked;
 Idle air channel is blocked;
 Air filter is blocked, leaky or not installed;
 Fuel tank vent is blocked;
 Fuel pump fails;
 Throttle body assembly fixer is loosened;

Vent pipe fixer is loosened.
Cylinder pressure is too low:
 Spark plug is loosened;
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Benelli TNT125 Specifications

General

Displacement	125 cc
Transmission	5-speed
Fuel System	EFI
Fuel Capacity	7.2 liters
Seat Height	780 mm
Dry Weight	116 kg
Bore x Stroke	54 mm x 54.5 mm
Starting System	Electric
Wheelbase	1215 mm
Engine Type	Single cylinder, 4-stroke, air-cooled
Front Suspension	Upside-down fork
Front Brake	Single disc
Rear Brake	Single disc
Front Tire	120/70-12
Rear Tire	130/70-12
Max Power	8.2 kW (11.1 Cv) @ 9500 rpm
Rear Suspension	Swing arm with lateral shock absorber with adjustable spring preload