Assembly And Adjustment; Bottom End - Yamaha BR250F Service Manual

2-3. ASSEMBLY AND ADJUSTMENT
Tightening torque:
1.5 m-kg (10.8 ft-lb)
2. Thoroughly oil the bearing and the con-
necting rod.
3. Apply Yamabond 4 to the mating sur-
faces of the crankcase halves. Use
enough Yamabond to completely seal
the crankcase. An air leak can lead to
severe engine damage.
4. Carefully fit the lower crankcase half
onto the upper half. The oils seals and
the bearings must be properly seated in
both crankcase halves. Place the wire
bracket on the rear crankcase bolt as
shown in the photograph. Torque the
fou r crankcase bolts to specification.
5. Install the engine bracket onto the
crankcase. Torque the four bolts to
specification.
R/H
Right side
0.02 mm (0.0008 in)
80 mm (3.1 in)
Deflection tolerance
Left side
100 mm (3.9 in)
0.02 mm (0.0008 in)
LlH
c. Check the crankshaft assembly runout
with a dial gauge. If the ru nout is not
within specification, the crankshaft parts
are not properly aligned. To correct this
misalignment, tap the flywheel with a
brass hammer. Use a wedge if necessary.
A. Botton End
1. Place the crankshaft in the upper crank-
case half. Be sure the lip of each oil seal
and the nylon bearing support for the
right crankshaft bearing are properly
seated in the crankcase. The open side
of the bearing support must face the
front of the engine.
Tightening torque:
First 1.0 m-kg (7.2 ft-Ib)
Final 2.5 m-kg (18 ft-Ib)
2-12