Honda CB HORNET 160R 2015 Shop Manual page 121

Using 32 degree cutter, remove top 1/4 of the existing
valve seat material.
TOOLS:
Flat cutter, 27 mm (EX) 07780-0013300
Flat cutter, 30 mm (IN) 07780-0012200
Cutter holder 07781-001040
Using 60 degree cutter, remove the bottom 1/4 of the old
seat.
Remove the cutter and inspect the area you have just
removed.
TOOLS:
Interior cutter, 26 mm (EX)
Interior cutter, 30 mm (IN)
Cutter holder
Install a 45 degree finish cutter and cut the seat to proper
width.
Make sure that all pitting and irregularities are removed.
Refinish if necessary.
STANDARD SEAT WIDTH:
0.9 – 1.1 mm (0.035 – 0.043 in)
After cutting the seat, apply lapping compound to the valve
face and lap the valve using light pressure.
• Excessive lapping pressure may deform or damage
the seat.
• Change the angle of lapping tool frequently to prevent
uneven seat wear.
• Lapping compound can cause damage if it enters
between the valve stem and guide.
After lapping, wash any residual compound off the cylinder
head and valve.
Recheck the seat contact after lapping.
07780-0014500
07780-0014000
07781-001040
CYLINDER HEAD/VALVES
OLD SEAT
WIDTH
32°
OLD SEAT WIDTH
60°
SEAT WIDTH
45°
HAND LAPPING TOOL
7-17