We measure our clearances 0.400″ from the bottom of the skirt. What we have found works best is to find different pieces of paper in varying thickness, measure with a micrometer and write the thickness on the paper. If the piston falls through it’s got more clearance. If it stops in the bore it’s about right, and if it must be pushed through it needs more clearance to match the paper.
| Bore | Cast Iron Liner | Aluminium Liner | Ring End Gap Min. | Head | Valve – Intake | Valve – Exhaust |
|---|---|---|---|---|---|---|
| 89mm | 0.0015” – 0.002” | 0.016” | 0.055″ – 0.060″ | 0.060″ | 0.090″ | |
| 94mm | 0.0015” – 0.002” | 0.018″ | 0.060″ – 0.065″ | 0.060″ | 0.090″ | |
| 97mm | 0.0015” – 0.002” | 0.019” | 0.065″ – 0.070″ | 0.060″ | 0.090″ | |
| 98mm | 0.004” | 0.019” | 0.065″ – 0.070″ | 0.060″ | 0.090″ | |
| 99mm | 0.0045” | 0.020” | 0.065″ – 0.070″ | 0.060″ | 0.090″ | |
| 100mm | 0.005″ | 0.022” | 0.065″ – 0.070″ | 0.060″ | 0.090″ | |
| 102mm | 0.022” | 0.065″ – 0.070″ | 0.060″ | 0.090″ | ||
| 103.1mm | 0.0055” | 0.022” – 0.024” | 0.065″ – 0.070″ | 0.060″ | 0.090″ |
With any of the engines, the cam bolt and lock washer should be replaced
frequently. Be sure to use a liberal amount of blue Loctite on the cam bolt and
torque to the specifications in the manual.
Timing checked at 0.040 in. (1 mm) lift, 0.00 clearance
Running clearance 0.004 in. (0.1 mm)
| Cam | Lift | Duration | Open | Close | |
|---|---|---|---|---|---|
| 660 | 7.9mm | 225° | 2.5° BTDC 42.5° BBDC |
42.5° ABDC 2.5° ATDC |
IN EX |
| 665 | 7.8mm 7.87mm |
240° 225° |
4° BTDC 36.5° BBDC |
56° ABDC 8.5° ATDC |
IN EX |
| 667 | 229° | ||||
| 670 | 8.9mm | 261° | 13.5° BTDC 90.5° BBDC |
67.5° ABDC 20.5° ATDC |
IN EX |
| 675 | 9.65mm 9.56mm |
297° 285° |
45.5° BTDC 74.5° BBDC |
71.5° ABDC 30.5° ATDC |
IN EX |
| 700 | 220° 240° |
||||
| 800 | 9.3mm | 249° | 12° BTDC 55° BBDC |
57° ABDC 14° ATDC |
IN EX |
| 802 | 249° 260° |
||||
| 805 | 9.64mm | 248° | 12° BTDC 54° BBDC |
56° ABDC 14° ATDC |
IN EX |
| 860 | 10.55mm | 292° | 44° BTDC 72° BBDC |
68° ABDC 40° ATDC |
IN EX |
| 865 | 9.67mm | 269° | 20° BTDC 65° BBDC |
69° ABDC 24° ATDC |
IN EX |
| MC x6 | 0.450″ | 264° | 24° BTDC 60° BBDC |
60° ABDC 24° ATDC |
IN EX |
| MC x11 | 0.420″ 0.405″ |
278° 274° |
33° BTDC 66° BBDC |
65° ABDC 31° ATDC |
IN EX |
| MC x20 | 0.450″ 0.422″ |
290° 292° |
42.5° BTDC 63.5° BBDC |
67.5° ABDC 38.5° ATDC |
IN EX |
| Part | Wire Coler | Resistance |
|---|---|---|
| Trigger Coil | ||
| High Speed | Black -> Pink | 12-20 Ω |
| Low Speed | Black -> Blue | 120-180 Ω |
| Stator | ||
| Low Speed Charging Coil | Black -> Brown | 230-350 Ω |
| High Speed Charging Coil | Brown -> Red | 4-6 Ω |
| Lighting Coils | White -> Orange | 0.6-0.9 Ω |
| White -> Green | 0.54-0.8 Ω | |
| Green -> Orange | 0.8-1.6 Ω | |
| Ignition Coil | ||
| Primary Winding | Core -> Orange | 0.95-1.1 Ω |
| Secondary Winding | High Tension Wire -> Black | 11-12k Ω |
Crankshaft
Width (Nominal): 74.95mm (2.950″) to 75.05mm (2.954″)
Runout: Max 0.05mm (0.002″)
End Play: 0.1mm (0.004″) to 0.4mm (0.0157″)
Connecting Rod
Radial Play: Max 0.05mm (0.002″)
Axial Play: 0.60mm (0.0236″) to 0.93mm (0.0356″)
Axial Wear Limit: Max 1.4mm (0.0551″)
Small End ID: 22.02mm (0.8669″) to 22.04mm (0.8677″)
Piston Pin OD: 22mm (0.8661) +0.0mm (0.00″) / -0.004mm (0.0015″)
Clearance: 0.02mm (0.0007″) to 0.044mm (0.0017″)
Balancer
End Play: 0.1mm (0.004″) to 0.2mm (0.008″)
Oil Pump
Rotor Tip: 0.01mm (0.0003″) to 0.1mm (0.0039″)
Housing: 0.11mm (0.0043″) to 0.19mm (0.0074″)
End Clearance: 0.02mm (0.0008″) to 0.09 (0.0035″)
Transmission Shaft
End Play: 0.1mm (0.004″) to 0.2mm (0.008″)