ENGINE ASSEMBLY AND ADJUSTMENT
A. Important Information
1. Gasket and seal
All gaskets and seals should be replaced when an engine is overhauled. All gasket surfaces and oil seal lips must be cleaned.
2. Properly oil all mating engine and transmission parts and bearings during reassembly.
3. Circlip
6. Middle gear (installation only, refer to page 67 for the middle gear adjustment)
a. Install the middle drive gear assembly with the proper size of shim(s) and secure it with the bearing retainers and new "TORX" screws.
Tightening torque: 2.5 m-kg (18 ft-lb)
1. Shims
13. Remove the front cylinder holding nut and remove the cylinder assembly. It may be necessary to tap the cylinder lightly to loosen it from the base gasket.
14. Remove the rear cam chain guide by loosening the holding bolt.
1. Holding bolt 2. Rear cam chain guide
2. Lower crankcase
a. Install the shift cam and secure it with the guide pin. Install the stopper plate and bolt and tighten securely.
b. Install the neutral switch.
c. Install the transmission drive axle assembly into the crankcase.
ENGINE OVERHAUL
A. Cylinder Head and Cylinder
1. Remove the cylinder head cover.
2. Remove the left crankcase cover (pickup coil cover).
3. Remove the cam chain tensioner.
5. Clutch assembly
a. Install the thrust plate onto the transmission main axle.
1. Thrust plate
b. Install the oil pump drive sprocket onto the main axle without the spacer collar and place the oil pump drive chain on its sprocket.
1. Oil pump drive sprocket
L. Lower Crankcase
1. Remove the dowel pin and "O-ring".
2. Remove the shift fork guide bar and shift forks. The shift forks are identified by numbers cast on their sides.
3. Remove the bolt securing the shift cam locating pin and remove the stopper plate and locating pin.
4. Remove the neutral switch.
C. Middle Gear Servicing
1. Disassembly
Refer to page 39 for disassembly.
2. Inspection
Refer to page 52 for inspection.
3. Gear lash check
NOTE:---------------------------------------------------
L. Transmission
1. Inspect each shift fork for signs of galling on gear contact surfaces. Check for bending. Make sure each fork slides freely on its guide bar.
2. Roll the guide bar across a surface place. If the bar is bent, replace.
3. Check the shift cam grooves for signs of wear or damage. If any profile has excessive wear and/or damage, replace cam.
I. Crankshaft
1. Crankshaft run-out
Support the crankshaft at both ends on V-blocks. Measure the amount of crankshaft run-out on the main bearing journals with a dial gauge while rotating crankshaft.
Run-out limit: 0.040 mm (0.0016 in!
If run-out exceeds limit, replace crankshaft.
2. Inspection of bearings