Poor Performance At Low Speed And Idling - DAELIM HISTORY 125 Service Manual

POOR PERFORMANCE AT LOW SPEED AND IDLING

Smoothly accelerate engine.
Engine speed increases.
Check the ignition timing.
Normal
Strongly kick the starter pedal, and the
cylinder compression.
Normal
Check the carburetor for clogging.
Not clogged
Check the spark plug.
Not contaminated or not discolored.
Check for engine overheating.
Not overheated.
Accelerate suddenly or run at
Engine does not knock.
Accelerate
Completion
Engine speed does not
increase sufficiently.
Abnormal
Low
Clogged
Contaminated or
discolored.
Overheated
Engine knocking
TROUBLESHOOTING
CAUSE OF TROUBLE
·Clogged air cleaner.
·Insufficient fuel supply.
·Clogged fuel tank cap air hole
·Clogged muffler.
·Faulty CDI unit.
·Faulty A.C generator.
·Worn cylinder or piston ring.
·Damaged cylinder head gasket.
·Cracked cylinder or cylinder head.
·Poor carburetor maintenance.
·Poor plug maintenance
·Using spark plug with an incorrect
heat range.
·Lean mixture.
·Worn cylinder or piston
·Lean fuel mixture
·Poor quality fuel being used.
·Excessive carbon build-up on
combustion chamber.
·Incorrect ignition timing.
·Damaged cooling fan.
·Excessive carbon build-up on
combustion chamber.
·Poor quality fuel being used.
·Lean fuel mixture.
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