![background image](http://html1.mh-extra.com/html/cobra/cx50-jr-2015/cx50-jr-2015_owners-manual_2630602049.webp)
INSPECTION NOTE:
Inspect the piston for abrasions and deposits on the top and sides and clean or
replace as necessary.
INSPECTION NOTE:
Piston ring end gap should be between 0.006” (0.16 mm) and 0.020” (0.5 mm)
Splitting the Cases
1. Remove the fasteners holding the two halves of the crankcase together.
2. Separate the cases with a proper case splitting tool.
CAUTION:
Take caution when handling the crankshaft. It is the main power transfer to the
rest of the engine. If it is out of alignment, it will cause premature failure of your
bearings which can lead to serious damage to the cylinder as well as the rest of
the engine. Do not try to true the crank yourself. Truing the crank should be
done professionally.
CAUTION:
•
If you split the cases, check the gear tooth faces for chipping & signs of
fatigue.
•
Check the small needle bearings for fatigue. If the bearings are damaged,
the engine cases should be checked to make sure the needle-bearing casing
didn’t oblong the bearing hole in the case.
•
Needle bearings should be replaced every 2 months.
Engine Assembly
CAUTION:
For any seals that are to be installed, apply a light amount of grease to the seals’
ID, assembly lube on all bearings and a small amount of Loctite to the OD.
1. Press the three bearings into the respective holes in each case half.
2. Press in the crank seals such that the concave side faces the crank weights.
3. Press in the counter shaft seal (concave side faces inside of transmission)
4. Press in the water pump assembly
5. Tap both ways axially then verify easy rotation.
6. Inspect the crankshaft for proper true geometry
(no more than 0.002 “, 0.05mm, measured at
bearing journal area while supported from the
ends).
7. Insert case bolts with the proper lengths at the
locations shown.
8. Torque to 12Nm (105in-lb) in the pattern shown
here.