Yamaha WR450F Owner's Service Manual page 62

Starter motor
Power output
Armature coil resistance
Brush overall length
Limit
Brush spring force
Commutator diameter
Limit
Mica undercut (depth)
Starter relay
Amperage
Coil resistance
Starting circuit cut-off relay
Coil resistance
Headlight relay
Coil resistance
Fuses
Main fuse
Radiator fan motor fuse
Spare fuse
ELECTRICAL SPECIFICATIONS
0.48 kW
0.0117–0.0143 
7.0 mm (0.28 in)
3.50 mm (0.14 in)
3.92–5.88 N (400–600 gf, 14.11–21.17 oz)
17.6 mm (0.69 in)
16.6 mm (0.65 in)
1.50 mm (0.06 in)
180.0 A
4.18–4.62 
75.7–92.5 
75.7–92.5 
15.0 A
5.0 A
15.0 A
2-11