Honda GX 120 Tech Manual page 12

IN TAKE
0.050"
0.100"
0.150"
0.180 Split
0.200"
Maxlift .227" Peak 104 - 107 ATDC
0.200"
0.180 Split
0.150"
0.100"
0.050"
FLYWHEEL, FAN AND IGNITION SYSTEM
Caution should be used when removing flywheel. Do not hit with hammer or other heavy objects. Service manual
show flywheel to be removed with commercially available 6" puller. Another method is inertia type knocker that
threads onto crankshaft end.
The transistorized magneto ignition is fixed at 25 degrees BTDC and may not be altered in anyway. Firing
must not exceed 0.104" or 26 degrees BTDC.
Quick check: Turning flywheel clockwise-if the leading edge of the depression of flywheel rim where the
magnet is mounted is not still under the right hand coil leg at 0.115" BTDC, it is probably illegal and should be
checked further. If timing needs to be checked further see page 19.
A. Flywheel keyway or its position must not be altered.
B. Key may not be deleted or altered in any way.
C. Magnet and its position may not be altered in any way.
CAMSHAFT PROFILE LIMITS
Degrees
10.5 to 14 ATDC
26.5 to 30 ATDC
45 to 48.5 ATDC
71 to 74.5 ATDC
136 to 141 ATDC
162.5 to 167 ATDC
180.5 to 185 ATDC
197.5 to 201 ATDC
EXHAUST
0.050" 207 to 210.5
0.100" 190 to 193.5
0.150" 170.5 to 174.5
0.180 Split
0.200"
Maxlift .229" Peak 107.5 - 110.5" BTDC
0.200" 70.5 to 73.5
0.180 Split
0.150" 44.5 to 47.5
0.100"
0.050"
Degrees
BTDC
BTDC
BTDC
144 to 148 BTDC
BTDC
BTDC
26 to 29.5 BTDC
9 to 12.5 BTDC
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