Clutch Slips
If the engine speed increases without an increase
in motorcycle speed, the clutch is probably slipping.
Some main causes of clutch slipping are:
1. Incorrect clutch cable adjustment.
2. Weak clutch springs.
3. Worn clutch or friction plates.
4. Damaged pressure plate.
5. Clutch release mechanism.
6. Incorrectly assembled clutch.
7. Loose clutch nut.
8. Improper oil level.
9. Improper oil viscosity.
10. Engine oil additive being used (clutch plates
contaminated).
Clutch Drag
If the clutch will not disengage or if the bike
creeps with the transmission in gear and the clutch
disengaged, the clutch is dragging. Some main
causes of clutch drag are:
1. Incorrectly assembled clutch.
2. Uneven clutch spring tension.
3. Warped clutch plates or pressure plate.
4. Bent push rod.
5. Damaged clutch boss.
6. Damaged primary driven gear bushing.
7. Swollen friction discs.
8. Clutch marks not properly aligned.
9. Engine oil level too high.
10. Incorrect oil viscosity.
11. Engine oil additive being used.
GEARSHIFT LINKAGE
The gearshift linkage assembly connects the
shift pedal to the shift drum (internal shift mecha-
nism). The external shift mechanism can be exam-
ined after the clutch has been removed. The
internal shift mechanism can only be examined
once the engine has been removed and the crank-
case split.
Common gearshift linkage troubles and their
checks are listed below.
Transmission Jumps Out of Gear
1. Incorrect shift pedal position.
2. Bent or worn shift fork.
3. Bent shift fork shaft.
4. Gear groove worn.
5. Damaged stopper bolt.
6. Weak or damaged stopper arm spring.
7. Loose or damaged shift cam.
8. Worn gear dogs or slots.
9. Damaged shift drum grooves.
10. Weak or damaged gearshift linkage springs.
Difficult Shifting
1. Improperly assembled clutch or clutch master
cylinder.
2. Incorrect oil viscosity.
3. Bent shift fork shaft(s).
4. Bent or damaged shift fork(s).
5. Worn gear dogs or slots.
6. Damaged shift drum grooves.
7. Weak or damaged gearshift linkage springs.
Shift Pedal Does Not Return
1. Bent shift shaft.
2. Weak or damaged shift shaft spindle return
spring.
3. Shift shaft incorrectly installed.
4. Improper shift pedal linkage adjustment.
5. Bent shift fork shaft.
6. Damaged shift fork.
7. Seized transmission gear.
8. Improperly assembled transmission.
TRANSMISSION
Transmission symptoms are sometimes hard to
distinguish from clutch symptoms. Common trans-
mission troubles and their checks are listed below.
Refer to Chapter Seven for transmission service
procedures. Before working on the transmission,
make sure the clutch and gearshift linkage assem-
blies are working properly.
Difficult Shifting
1. Incorrect clutch adjustment.
2. Incorrect clutch operation.
3. Bent shift fork shaft.
4. Damaged shift fork guide pin(s).
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CHAPTER TWO