Special Tool - Outside Circlip Pliers: 57001-144
The 5th gear [A] on the output shaft has three steel balls assembled into it for the positive neutral finder mechanism.
Remove the 5th gear as follows.

Set the output shaft in a vertical position holding the 3rd gear [B].
Spin the 5th gear quickly [C] and pull it off upward.
Transmission Assy Installation
Transmission Shaft AssemblySeat Cover Removal
Remove:
Rear Seat (see Rear Seat Removal)
Remove the bolts [A].
Remove the upper seat cover backward [B] to clear the
hook portions.
Remove:
Front Seat (see Front Seat Removal)
Quick Rivets [A]
Bolts [B]
Seat Covers [C]
...
Water Pump Housing Disassembly
NOTICE
Do not damage the hole wall of the water pump
housing.
Insert a bar [A] into the pump housing [B], and hammer
evenly around the circumference of the mechanical seal
bottom [C].
Take the oil seal [A] out of the housing [B] with a hook [C].
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Inquiries to Rider
Each rider reacts to problems in different ways, so it is important to
confirm what kind of condition
the rider is dissatisfied with.
Try to find out exactly what problem occurs under exactly what
conditions by asking the rider; knowing
this information may help you reproduce the prob ...