Piston with new cylinder when assembling: 0.06 to 0.07 mm
Wear limit between the piston and its cylinder: 0.12 mm
Maximum cylinder taper: 0.04 mm
Maximum ovalization: 0.04 mm
The measurement of the piston is referred to 12/13 mm from the base of the
mantle
Piston rings: the installation 0.35 mm, wear limit 0.40 mm.
Crankshaft: maximum off-center of a new crankshaft when assembling: 0.01 mm
maximum off-center allowed when used: 0.04 mm
Axial rod movement: wear limit 0.04 mm.
ROUTINE MAINTENANCE
Every 25 hours: check spark plug gap and possible recovery to the correct value:
from 0.4 to 0.45 mm.
Every 50 hours: replace the spark plugs, control the engine torque mount screws.
After the first 250 hours: disassemble the heating units and control the tolerance.
If the readings data are 80% of the wear limit, replace the components with high
value. Change the reed valves petals.
The TBO of the engine is done 400/500 hours, depending on usage. We suggest to
remove the engine and send it to the factory or at a qualified service center to serve
a general recovery. Our engines are built with the finest Italian metals on the
market. These basic conditions are in particular so that many do not wear out,
reducing by more than 50% the cost of repairing the engine.
BELT TENSION
WARNING: THE ENGINE HAS TO BE OFF AND COLD
During operation, the belt is subjected to traction and wear, it follows that an
extension could lead to his slip on the pulleys as to reduce the overall performance
of the engine.
To restore the proper tension, loosen the screw M8 (No. 77) on the foot that shuts
the engine and the cam pulley with a torque wrench to turn the screw counter-
clockwise M12 (No. 74) by a force of 2.4 kgm, tighten the M8 (No. 77).
