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.
J. Oil Pump
1. Check the clearance between housing and outer rotor.
Standard clearance B : 0.03 ~ 0.08 mm (0.0012 ~ 0.0031 in)
2. Check the clearance between outer rotor and inner rotor.
Standard clearance: 0.03 - 0.09 mm (0.001 - 0.003 in)
3 Check the rotor to housing clearance using a straight-edge.
Standard clearance: 0.03 - 0.08 mm (0.001 - 0.003 in)
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: 0.030 mm (0.0012 in)
If run-out exceeds limit, replace crankshaft.
2. Inspection of bearings
. Cylinder
1. Inspect the cylinder walls for scratches. If vertical scratches are evident, the cylinder wall should be rebored or the cylinder should be replaced.
2. Measure cylinder wall wear as shown. If wear is excessive, compression pressure will decrease. Rebore the cylinder wall and replace the piston and piston rings. Cylinder wear should be measured at three depths with a cylinder bore gauge. (See illustration.)
D. Valve Spring and Lifters
1. Checking the valve springs
a. This engine uses two springs of different sizes to prevent valve float or surging. The valve spring specifications show the basic value characteristics.
INSPECTION AND REPAIR
A. Cylinder Head Cover
Place head cover on a surface plate. There should be no warpage. Correct by re-surfacing as follows:
Place #400 or #600 grit wet sandpaper on surface plate and re-surface head cover using a figure-eight sanding pattern. Rotate head cover several times to avoid removing too much material from one side.
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.
H. Oil Pump Removal and Disassembly
1. Remove the strainer cover. Note the wire harness clip position.
2a. Remove the oil pump securing bolts and remove the sprocket cover and oil pump assembly.
2b. Remove the Oil pump drive sprocket (1), Chain (2) Collar (3) and thrust plate.
C. Piston
1. Mark each piston to aid in reassembly.
2. Place a clean towel or rag into the crank-case to keep circlips and material from falling into the engine.
3. Remove piston pin clips, piston pins, and pistons.
D. Pick-up Coil Assembly
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