Honda 2010 CBF 250, Workshop Manual

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CYLINDER HEAD/VALVES
CBX250
SPECIAL TOOLS
Valve spring compressor 07757-0010000
Accessory of the compressor of springs 07959-KM30101
Driving guide of valves, 5.0 mm 07942-MA60000
Protector of the accommodation of accinador, 24 x 25.5 mm 07HMG-MR70002
Reamer of guides to valve, 5.0 mm 07984-MA60001
Valve seats
– Seat of the valve, 24 mm (45° ESC)
07780-0010600
– Seat of the valve, 27,5 mm (45° ADM) 07780-0010200
– Fresa plana, 24 mm (32° ESC) 07780-1250000
– Fresa plana, 27 mm (32° ADM) 07780-0013300
– Fresa interna, 26 mm (60° ESC) 07780-0014500
– Fresa interna, 37,5 mm (60° ADM) 07780-0014100
– Soporte de fresa, 4,5 mm 07781-0010600
INVESTIGATION OF PROBLEMS
•The problems of the top of the engine generally affect the performance. That can be diagnosed through the compression test, or da
use of a stethoscope to detect noises in the engine. •In case of the performance is deficient abajas rotations, check to see if there
are white smoke in the breather tube from the casing of the engine. If the tube presents smoke, verify if any ring of the
piston is jammed (page 8-6).
Compression too low, start difficult or poor performance at
low rotation.
• Valves
– Valves burned or bent
Synchronisation
incorrect valves
Spring of the valve broken
irregular Settlement of the valve
• Cylinder head Damage or leaks in the gasket of the cylinder head
Cylinder head bent or cracked
Spark plugof turning loose
Problems in the cylinder, piston or rings of the piston (Section 8)
Compression too high, overheating or timing
•Excessive Formation of carbon in the head of the piston or in the com-
bustion chamber.
Excessive Smoke
• Cylinder head
– Stem or guide to valves worn
– Checkpoints of oil from the shoots damaged
– Problems in the cylinder, piston or rings of piston (Section 8)
Excessive Noise
• Cylinder head:
– Incorrect Setting valves
–Valves stalled or springs of valves broken
– Camshaft damaged or worn
– Distribution Chain loose or worn
– Distribution Chain damaged or worn
– Tensile distribution chain worn or damaged
– Teeth the spiral of distribution worn
– Tumbler and/or axle of the rocker worn
– Actuating the valve damaged or worn
• Problems in the cylinder, piston or rings of the pis-
ton (Section 8)
Irregular Idling
• Cylinder with low compression