Sachs Bikes madass, Repair Instructions

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CYLINDER / PISTON
SERVICE INFORMATION
GENERAL
- This section covers the Service of the piston and cylinder. These Services are completed with the engine in the frame.
- The camshaft lubricating oil is fed to the cylinder head through an oil orifi ce in the right crankcase. Be sure this orifi ce is not
clogged and that the O-ring and dowel pins are in place before installing the cylinder.
SERVICE DATA Unit: mm
ITEM STANDARD SERVICE LIMIT
Cylinder I.D. 39.005-39.01 5 39.05
Warpage — 0.05
Out of round — 0.10
Taper — 0.10
Piston O.D. 38.975-38.995 38.90
Piston pin bore 13.002-13.008 13.05
Cylinder-to-piston clearance 0.010-0.045 0.15
Piston pin O.D. 12.994-13.000 12.98
Piston-to-pin clearance 0.002-0.014 0.08
Piston ring End gap Top/second 0.15-0.35 0.5
Oil (side rail) 0.30-0.90 1.1
Piston-to-ring
groove clearance Top 0.015-0.050 0.12
Second 0.015-0.050 0.12
Connecting rod small end I.D. 13.016-13.034 13.06
Small end-to-piston pin
clearance 0.016-0.040 0.08
TORQUE VALUES
Cylinder bolt 10-12 Nm
Cam chain guide roller pin bolt 10 Nm
TROUBLESHOOTING
Low or unstable compression
- Worn cylinder or piston rings
Excessive smoke
- Worn cylinder, piston or piston ring
- Improper Installation of piston rings
- Scored or scratched piston or cylinder wall
Overheating
- Excessive carbon build-up on piston or combustion cham-ber wall
Knocking or abnormal noise
- Worn piston and cylinder
- Excessive carbon build-up