Engine Element Control; Balance Weight, External Dimension Control; Connecting Rod Radial Clearance; Connecting Rod Head Side Play - SHERCO ST Series Workshop Manual

ENGINE ELEMENT CONTROL

❱❘ Balancing weight, external dimension control
• With a caliper, measure the outside distance of
the balancing weights
.
External value :
125cc 54.85mm +0 / -0.2
250/300cc
❱❘ Connecting rod radial clearance
Place the crankshaft on V and place a dial
•
gauge [A] against the big end.
• Push [B] the big end towards the gauge, then in
the opposite direction.
• The difference between these two
measurements corresponds to the radial
clearance.

Connecting rod radial clearance:

Standard : 0.015 mm – 0.025 mm
Limit : 0.06 mm
If the radial clearance is greater than the
tolerated limit, the crankshaft must be replaced
❱❘ Connecting rod end side clearance
Measure the side play of the big end
•
Connecting rod end side clearance :
Standard : 0.4 mm – 0.6 mm
Limit : 0.8 mm
If the play is above the tolerated limit, replace
the crankshaft
❱❘ Crankshaft runout control
• Place the crankshaft on an alignment device or
V-shaped shims, and place a comparator as
shown in the image in position [A].
• Then slowly turn the crankshaft. The maximum
difference between the measurements
corresponds to the offset of the crankshaft.
Crankshaft Offset:
Standard: 0.03 mm
27
60.00mm +0 / -0.2
[A]
Limit: 0.05 mm
B
ST SERIES
A