Gear Sh).Ft Mechanism - Honda ST50 Shop Manual

Reu:Kmbly
Perform the reassembly in the reverse order of disassembly.
Note:
J. Note the right po,sition of each component rcfering IO Fig. 47~50.
2, Replace all circllp!I with new ones.
29
3. After combining the right crankcase with the left crankcase, check 1he transmission
if
It engages smoothly
iogean.
3.9 Gear Shift Mechanism
De:saiptlon
The gear spindle arm which is co nnected to the gear shift spindle rotates the gear shift drum and this
causes the gear shirt fork to move left and right in the drum groove. The gear shift fork is controlled
by the groove in the drum and this in ium causes the gears to slide and change gears.
Disassembly
I.
Refer to the section on crankshaft disassembly
on page
24.
By removing the right crankcase,
the gear shift drum and the fork assembly
can be removed wit h 1hc transmission gear
asacomplc tcuni1.
Inspection
I. Mcasuringgear shiftforkcnd thickness.
Thcshifl fork end thickness is measured with
a micrometer (Fi~. 49).
mm (inch)
Ri&ht side
Left
side
- ~
s.s~6.3
(0. 217~0.248)
4. i~S.3
(0.l77~0.20ll)
Scrv1cea c L1m1t
Replace 1f
under
S.3(0.20ll)
cpace1 uncr
4.3(0. 169)
2. Measuring the inside dian1e1er of the gear
shift fork.
The inside diameter of the gear shirt fork is
measured with a cylinder gauge or an inside
micrometer (Fig. 50).
Standard Value
34.0-34. 0l
(1.3J8S~l.339 S)
inch{mm)
ScTV10C1ble
Limn
Replace if over
34.2(1.347)
3. Measuring the outside diameter of
the gear
shift drum
The diameter is measured with a micromete r
(Fig. 51).
Si.andard value
33. 9S~3l.98
(1 . )366--1.3377)
mm
(inch)
Scrvicc:ablc U111.11
Replace if under
33.9(1.335)
4. Check the fork end for bend ing.
Flg.49