BSA D14/4 BANTAM SUPREME D14/4 BANTAM SPORTS, Руководство по ремонту

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D14/4 ENGINE B14
Having checked the flywheels for concentricity, it
will now be necessary to check the end float of the
shafts. Place a ·010" shim on the right-hand spindle
and insert it through the main bearings and oil seal in
the case. Fit the left-hand oil seal, bearing and case,
and temporarily screw the case halves together.
Measure the amount of end float on the flywheel
shafts, which should be between ·004" and ·006".
Remove the left-hand crankcase and fit the required
shims to the shaft, next to the flywheel. The shims are
available in the following sizes: ·001" (90-0152),
·004" (90-0153), ·005" (90-0154), and ·010" (90-
0155). Part numbers are shown in brackets.
If, during dismantling, the flywheel assembly was
not disturbed, the standard ·010" shims can be
replaced in their original positions.
BEFORE ASSSEMBLY
Before assembly all components should be thoroughly
cleaned and checked for signs of wear. All joint faces
should be cleaned of all old jointing compound, and if
possible the crankcase halves should be lightly lapped
together to check for distortion. Carefully examine all
threads, bushes and bearings.
The flywheel assembly runs on three ball bearings,
two on the drive-side and one on the generator side.
Before trying to remove these bearings it is advisable
to warm the crankcase halves. The bearing on
generator side, and the outer bearing on the drive-side
are both retained by circlips, and can therefore only be
knocked out from one side.
Whenever the engine is stripped it is advisable to
replace all oil seals.
ENGINE ASSSEMBLY
Fit the gearbox mainshaft through its bearing in the
right-hand crankcase, and grip the mainshaft in a soft-
jawed vice.
Assemble the clutch drum and kickstart ratchet
pinion, having first checked the ratchet teeth for signs
of wear.
The kickstarter ratchet engages on the clutch drum and
is followed by a spring, a retainer, and the circlip.
Check that the ratchet spins freely on the clutch drum.
Slide the hardened steel thrust washer over the
mainshaft, followed by the cylindrical mainshaft bush.
Replace the clutch drum. Grease the thrust bearing, the
two large steel washers and assemble the "sandwich"
on to the clutch centre. Slide the assembly carefully on
to the mainshaft splines taking care not to trap the
needle trust bearing. Fit the steel washer and nut and
taking care that the clutch drum spins freely, fully
tighten the clutch center nut.
If it was removed, replace the gearchange cam plate
plunger socket together with spring, ball, and a little
grease.
Place the layshaft first gear in position and prepare
to assemble the selector forks. The forks are handed,
and when the two flat edges are together the roller
pegs should be in line. Lightly grease the rollers, and
assemble on the pegs and fit the selector forks on to
the selector fork spindle.
Assemble the cam plate, quadrant and mounting
bracket, ensuring that the center of the gear lines up
with the centre line of the small hole in the quadrant,
and the neutral slot.
FIG. B16.