tion so the neutral knob (A,
Figure 89
) on the drum
aligns with the neutral switch (B) in the crankcase.
11. Install the center shift fork (
Figure 82
) into the
mainshaft second-third combination gear. Rotate
the shift fork so its guide pin engages the groove in
the shift drum.
12. Install the shift fork shaft (
Figure 80
) through
the shift forks. Rotate the shaft as necessary so the
cutout in the shaft faces the countershaft, and seat
the shaft into the crankcase boss.
13. Spin the transmission shafts and use the shift
drum to shift through the gears. Make sure you can
shift into all gears. This is the time to find a problem
with the transmission, not after the engine is assem-
bled and installed in the frame.
14. Once it is confirmed that the transmission shifts
normally, shift it into neutral.
15. Install the middle driven gear (B,
Figure 79
).
Align the internal splines of the gear with those of
the middle drive shaft and lower the middle driven
gear into place so its bearing bottoms in the boss.
16. Install the middle drive gear (A,
Figure 79
)
onto the countershaft. The splines of the gear must
engage those of the countershaft, and the middle
drive gear teeth must mesh with the teeth of the
middle driven gear.
17. Install the two dowels (A,
Figure 77
) into the
crankcase mating surface.
18. Lubricate a new O-ring with lithium soap
grease. Install the O-ring onto the short collar and
seat the assembly (B,
Figure 77
) in the boss beneath
the crankshaft web.
19. Lubricate a new O-ring with lithium soap
grease and install the O-ring (C,
Figure 77
) into the
crankcase mating surface.
20. Check the left and right crankcase mating sur-
faces for old sealant material or other residue. Clean
them as necessary.
21. Apply engine oil to the transmission shafts and
journals in the left case half. Also lubricate the bear-
ings, including the inner races, in the right crank-
case half. Do not add so much oil that it will drip
from the bearing when the case half is turned over.
22. Apply a light coat of Yamaha Bond No. 1215
(part No. ACC-1100-15-01 or 90890-85505) or on
equivalent sealant to the mating surface of the left
crankcase half. Make the coating as thin as possible
while also completely covering the mating surface.
23. Lower the right crankcase half onto the left
case half until it is completely seated. If the right
case will not seat on the left, remove the right case
and determine the source of the obstruction. Do not
use the crankcase bolts to pull the cases together.
Pay attention to the following:
a. Align the bearings in the right case half with
their respective assemblies in the left case
half.
b. Rotate the shift drum so the ramps on the shift
cam align with the cutouts in the right crank-
case half.
24. Install the right crankcase bolts (
Figure 76
).
Tighten the bolts enough to hold the cases together
while they are turned over. These bolts will be
torqued after the left crankcase bolts are tightened.
Note the following:
a. The silver colored bolts must be installed in
the No. 15 and 16 positions.
b. Install a new copper washer with bolt No. 15.
c. Install the engine ground wire with bolt No.
18. Position the wire so its free end extends
up above the top of the crankcase.
25. Install the shift fork shaft retainer (
Figure 75
).
Apply a high-strength threadlocking compound to
the retainer screws and tighten the screws securely.
ENGINE LOWER END
159
5
89
88
