APRILIA TUONO V4 R a-PRC ABS Service Station Manual page 354

Engine
It is fundamental that, in case of replacement of a
connecting rod, also the other one installed on the
same crankpin is always replaced:
•
if the piston 1 connecting rod is re-
placed, the one relative to piston 2
must also be replaced and vice versa;
•
if the piston 3 connecting rod is re-
placed, the one relative to piston 4
must also be replaced and vice versa;.
The connecting rod class is stamped on its left
side, viewed from the front, from the side with the
bevelling on the big end hole.
Bushing selection
CRANKSHAFT BUSHINGS
CRANKCASE CATEGORY
Three crankcase classes are available (A - B- C)
which differentiate in the diameter of the hole in the
bearings.
The category is marked on the crankcase, on the
right side, in the area below the crankshaft.
Different classes of bearings can be used (e.g.: A
- B - C or B - B - C or A - B - A ....).
ENG - 354
TUONO V4 R a-PRC ABS