If the surface is corroded or if the blades are damaged, replace the impeller

Water Pump Impeller Disassembly/Assembly
Water Pump Housing DisassemblyExhaust Device
This motorcycle is equipped with a
exhaust device system. This system
controls the valve in the exhaust pipe
and produces stable engine power at
low and middle engine speed. This exhaust
device is controlled by the ECU,
and adjustment or maintenance should
be done only by a competent mechanic ...
Lubrication
It is important to lubricate rotating or sliding parts during
assembly to minimize wear during initial operation. Lubrication
points are called out throughout this manual, apply
the specific oil or grease as specified.
Direction of Engine Rotation
When rotating the crankshaft by hand, the fre ...
Valve-to-Guide Clearance Measurement (Wobble Method)
If a small bore gauge is not available, inspect the valve
guide wear by measuring the valve to valve guide clearance
with the wobble method as indicated below.
Insert a new valve [A] into the guide [B] and set a dial
gauge against the stem perpendicular to it as close as
possible to the cy ...