Honda CBR125R, Руководство пользователя

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CYLINDER HEAD/VALVES
8-5
TROUBLESHOOTING
• Engine top-end problems usually affect engine performance. These problems can be diagnosed by a compression test,
or by tracing top-end noise with a sounding rod or stethoscope.
• If the performance is poor at low speeds, check for white smoke in the crankcase breather hose. If the hose is smoky,
check for a seized piston rings.
Compression too low, hard starting or poor performance al low speed
• Valves:
– Incorrect valve adjustment
– Burned or bent valve
– Incorrect valve timing
– Weak valve spring
– Uneven valve seating
– Valve stuck open
• Cylinder head:
– Leaking or damaged cylinder head gasket
– Warped or cracked cylinder head
– Loose spark plug
• Faulty cylinder, piston or piston rings (page 9-4).
Compression too high, over-heating or knocking
• Excessive carbon build-up on piston head or combustion chamber
Excessive smoke
• Worn valve stem or valve guide
• Damaged stem seal
• Faulty cylinder, piston or piston rings (page 9-4).
Excessive noise
• Incorrect valve adjustment
• Sticking valve or broken valve spring
• Worn or damaged camshaft
• Worn rocker arm and/or shaft
• Worn rocker arm and valve stem end
• Worn cam sprocket teeth
• Worn and loose cam chain
• Worn or damaged cam chain tensioner
• Faulty cylinder, piston or piston rings (page 9-4).
Rough idle
• Low cylinder compression
• Faulty fuel system
Compression gauge attachment
07RMJ-MY50100
or equivalent commercially avail-
able
Valve guide driver
07743-0020000