Yamaha BR250F - Disassembly; Inspection

A. Disassembly
1. Remove the secondary sheave from the
jackshaft (Refer
to 4-5, A "Removal.")
2. Remove the bearing cage from behind
the jackshaft bearing.
3. Disconnect the brake cable from the
handlebar.
It will be helpful to loosen
the cable at the caliper. The caliper need
not be disassembled.
4.
Place an oil pan beneath the drain hole
under the chain
case.
5. Remove the chain case cover, and let the
oil drain
into the oil pan.
6. Loosen the chain tension.
7. Remove the securing hardware and
washers
from both the drive and driven
sprockets.
8. Remove the drive chain and both
sprockets.
9. Remove the collar from behind
each
sprocket.
10. Remove the three
secu ring bolts and
remove the chain
case.
4-11
11. Remove the jackshaft from the left side
of the snowmobile.
B. Inspection
1. Inspect the brake disc. Place
it on a sur-
face plate and check around the edges
with a feeler gauge. If the gap is uneven,
the disc is bent and
must be replaced.
2. Inspect the bearing surfaces
of the jack-
shaft.
If worn or bent, replace the jack-
shaft.
3. Inspect the bearings in the chain
case.
If the movement is rough or uneven,
replace the bearings.
4. Inspect the drive and driven sprockets;
replace
if worn.