Engine Lacks Power - Honda 2000 XR50R Service Manual

TROUBLESHOOTING
ENGINE LACKS POWER
Possible cause
1, Raise wheel off the ground and spin - - - Wheels do not spin
freely---'~
. Brake dragging
by hand . Worn or damaged wheel bearing
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Wheels spins freely
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2. Check tire pressure - - - - - - - - -
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Pressure normal
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Pressure low - - - - - - -•• - . Faulty tire valve
· Punctured tire
3. Accelerate rapidly from low 1 0 - - - Engine speed doesn't
- ' Clutch slipping
second
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Engine speed reduced
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4. Accelerate lightly - - - - - - - - -
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'rn,
,p"d
;n"""
5. Check ignition t i m i n g l - - - - - - - - -
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Correct
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6. Test cylinder compression - - , - - - - - -
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Normal
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change accordingly . Worn clutch discS/plates
· Warped clutch discs/plates
· Weak clutch spring
· Additive in engine oil
Engine speed does not
--~.~
. Choke valve closed
increase . Clogged air cleaner
· Restricted fue l flow
· Clogged muffler
· Pinched fuel tank breather tube
Incorrect - - - - - - - - - - . . Faulty ignition control module
· Faulty ignition pulse generator
Incorrect - - - - - - - - - - • . Valve clearance too small
· Worn cylinder and piston rings
· leaking head gasket
· Improper valve timing
7. Check carburetor for clogging,----- Clogged - - - - - - - - -
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· Carburetor not serviced frequently
enough
Not clogged
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8. Remove spark plug
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- - - - - - - - - Fouled or discolored
----~.~
. Plug not serviced frequently enough
· Spark plug are the incorrect heat range
Not fouled or discolored
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9. Check oil level and condition - - - - - - Incorrect
--------~.~
. Oil level too high
I~I---
Correct . Contaminated oil
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10. Remove cylinder head
inspect lubrication
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cover and - - - Valve train not lubricated --~.~ . Clogged oil passage
properly . Clogged oil control orifice
Valve train lubricated properly
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