VESPA GTS 250 I.E. Workshop Manual page 152

Engine
- There are three crankcase versions: with RED
main bushings, with BLUE main bushings and with
YELLOW main bushings.
- There just one type of main bushing housing hole
in the crankcase
The standard diameter of the main bushings after
fitting is variable depending on a coupling selec-
tion.
- The bushing housings in the crankcase are avail-
able in two categories, Cat. 1 and Cat. 2, as are
the crankshafts.
- The main bushings are available in three thick-
ness categories, identified by colour markings, as
shown in the table below.
TYPE
A
B
C
Type "A"
- RED
Main half- 1.970
bearing 1.973
Bush- Crank- Internal bush-
ing cat- case
egory halves
category
A 1 29.025 29.040
B 1 29.019 29.034
2 29.028 29.043
C 2 29.022 29.037
Match the shaft with two category 1 crank webs
with the category 1 crankcase (or cat. 2 with cat.
2) Furthermore a replacement crankcase cannot
be matched with a crankshaft with mixed catego-
ries. The replacement crankshaft has half shafts
of the same category.
ENG - 54
IDENTIFICATION
RED
BLUE
YELLOW
Type "B" Type "C"
- BLUE - YEL-
LOW
1.9703 1.976
1.976 1.979
Possible
ing diameter fitting
after fitting
Original
Original
and spare
Original
Vespa GTS 250 I.E.