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1-2 Technical data
Model
SRM-3805
SRM-4605
Engine
Idling speed
rpm
2400 - 3000
Operating speed
rpm
6000 - 8000
Clutch-in speed
rpm
3300 - 3700
Compression pressure, standard kgf/cm
2
(psi)
7.5 (107)
8.0 (114)
Ignition system
Spark plug gap
mm(in)
0.6 - 0.7 (0.024 - 0.028)
Minimum secondary voltage at 1000 rpm
kV
15
Secondary coil resistance
k
Ω
1.0 - 1.5
Pole shoe air gaps
mm(in)
0.3 - 0.4 (0.012 - 0.016)
Ignition timing
°BTDC
25
Carburetor
Type
Diaphragm horizontal-draught
Supplier
Walbro WT-297
Walbro WT-120B
Venturi Size
mm(in)
11.11 (0.437)
12.7 (1/2)
Throttle Bore
mm(in)
15.85 (0.624)
15.85 (0.624)
Idle speed screw initial setting
turn in
2
2
H needle initial setting
turn back
1 1/2
1 1/4
L needle initial setting
turn back
1
1
Test Pressure, minimum
kgf/cm
2
(psi)
0.5 (7.0)
Metering lever height
mm(in)
1.65 (0.065) lower than diaphragm seat
BTDC: Before top dead center.
H needle: High speed needle.
L needle: Idle needle.
3
SERVICE INFORMATION
SRM-3805
SRM-4605