1 0 - jk-data
TRANSCRIPT
1 0 CRANKSHAFT/ • CONNECTING ROD
1.8-2.2kg-m (13.0-15.9ft-lbs)
~1
2.0-2.5kg-m(14.5-18.1 ft-lbs)
10-0
~ HONDA ~ CB750
--
~ HONDA ~ CB750 CRANKSHAFT/CONNECTING ROD
TROUBLESHOOTING 10-2
SERVICE INFORMATION 10-2
CRANKSHAFT REMOVAL 10-3
CONNECTING ROD REMOVAL 10-4
CRANKPIN OIL CLEARANCE INSPECTION 10-4
CONNECTING ROD ASSEMBLY 10-8
CRANKSHAFT ASSEMBLY 10-8
10-1
CRANKSHAFT/CONNECTING ROD
TROUBLESHOOTING Excessive Noise 1. Cran~shaft -Excessive crankshaft journal bearing play -Excessive crankpin bearing play
SERVICE INFORMATION
WORKING PRACTICE All bearing inserts are selective fit and are color coded. Select replacement bearing from color code table.
SERVICE DATA
Item Standard Crankshaft
Journal 0 .D. 35.985-36.000 mm (1.4167-1.4173 in.) Crank pin O.D. 35.985-36.000 mm (1.4167-1.4173 in.) Runout 0-0.03 (0-0.0012 in.) Connecting rod side clearance 0.15-0.30 mm (0.0059-0.0118 in.)
Crankcase
Upper case crankshaft holder width 22.85-22.90 mm (0.8996-0.9016 in.) Crankshaft oil clearance 0.020-0.046 mm (0.0008-0.0018 in.)
10-2
~ HONDA ~ CB750
Service Limit
35.940 mm (1.4150 in.)
35.940 mm (1 .4150 in.)
0.05mm (0.0020 in.) 0.40mm (0.0157 in.)
22.75mm (0.8957 in.)
0.08mm (0.0031 in.)
~HONDA ~ CB750
CRANKSHAFT REMOVAL
CRANKSHAFT/CONNECTING RO"O
If necessary, remove the cylinder head, cylinder and pistons. Separate the crankcase.
NOTE When the pistons are not removed, remove the connecting rod big end bearing caps.
Remove the mainshaft from the primary drive chains. Take out the crankshaft together with the primary drive chains.
UPPER CRANKCASE INSPECTION
Measure the. journal holder width of the upper crankcase.
SERVICE LIMIT: 22.75 mm (0.8957 in.)
CONNECTING ROD SIDE CLEARANCE
Inspect the connecting rod side clearance on the crankpin.
SERVICE LIMIT: 0.40 mm (0.0158 In.)
10-3
CRANKSHAFT/CONNECTING ROD
CONNECTING ROD REMOVAL Loosen connecting rod cap nuts. Remove the connecting rod bearings, and check for wear or damage.
CRANKSHAFT INSPECTION
Measure the crankshaft for runout.
SERVICE LIMIT : 0.05 mm (0.0020 In.)
CRANKPIN OIL CLEARANCE INSPECTION Assemble the connecting rod inserts in each rod cap. Place a plastigauge strip across each crankpin.
NOTE Clean all oil from the bearing inserts and crankpins.
Install each connecting rod on the corresponding crankpin and torque to specifications.
TORQUE: 1.8-2.2 kg-m (13.0-15.9ft-lbs)
10-4
Q.\ HONDA ~ CB750
W'\HONDA ~ CB750 CRANKSHAFT/CONNECTING ROD
Remove the caps and measure the plastigauge with the scale on the gauge bag.
SERVICE LIMIT: 0.08mm (0.0032 in.)
CRANKSHAFT JOURNAL OIL CLEARANCE
Put the lower bearing inserts in place and install the crankshaft. Put a piece of plastigauge across each journal, avoiding oil holes.
NOTE Wipe clean oil from the bearings and journals.
Install the lower crankcase. Install the mounting bolts and torque them evenly.
TORQUE: 2.0-2.5 kg-m (14.5-18.1 ft-lbs)
Remove the caps and measure the compressed plastigauge on each journal.
SERVICE LIMIT: 0.08 mm (0.0032 In.)
If the clearance exceeds the limit, the bearings should be replaced.
10-5
CRANKSHAFT/CONNECTING ROD
~HONDA. ~ CB750
CRANKPIN BEARING SELECTION
Determine and record each crankpin O.D. code number stamped on the crankweight on the drive sprocket side (or measure the crankpin O.D.)
Record the corresponding connecting rod I.D. code number (or measure it).
Cross reference the crank and bearing codes in the chart to determine the replacement bearing color.
Crankpin
Con- 0.0 necting rod big 36.000-end 1.0. 35.995
3 39.024 B (Brown) -39.016
39.016 ,----------, - 39.008
1 C (Green), L _________
39.008 0 (Yellow) - 39.000
Inspect the crankpin oil clearance.
STANDARD: 0.020-0.046 mm (0.0008-0.0018 In.)
10-6
4
35.995-35.990
B (Brown)
C (Green)
0 (Yellow)
5
35.990-35.985
A (Black)
B (Brown)
C (Green)
® /y,::::::r.t--L: ! 3 3 4 3 !
......___
(2) GENERATOR SIDE
(3)COLOR CODES
~HONDA ~ CB750 CRANKSHAFT/CONNECTING ROD
CRANKSHAFT JOURNAL BEARING CLEARANCE
Determine and record the main journal O.D. code letter stamped on the crankweight on the drive sprocket side.
Determine and record the corresponding upper crankcase bearing support code letter.
Cross reference the bearing support and crank codes to determine the replacement bearing color.
( I )UPPER CRANKCASE (Z)LOWER CRANKCASE
B 39.016 - 39.008
,-- -~--. : A : 39.008 t_ ____ J - 39.000
A
36.000-35.995
B (Brown)
C (Green)
D (Yellow)
Inspect the main bearing clearance.
STANDARD: 0.020-0.046 mm (0.0008-0.0018 In.)
1-----, l B : L-----•
35.995 -35.990
B (Brown)
C (Green)
C
35.990-35.985
A (Black)
B (Brown)
C (Green)
(1)CONTACK BREAKER SID
~ ~0 .
;;J) fl y (3)COLOR
CODES
Q)
L:IAABBB!
B
A
(2)GENERATOR SIDE ..... ;: APPLY THIN COATING OF ~ (
4) MOLYBDENUM
~ DISULFIDE GREASE
~
10-7
CRANKSHAFT/CONNECTING ROD
CONNECTING ROD ASSEMBLY Prior to assembly, ensure that the connecting rods have the same weight code letter. There are three weight code letters, D, F and J.
Install the bearing inserts, and bearing caps.
CAUTION Be sure bearing caps are installed in their correct location and the bearing pawls point to the front of the engine. Torque the cap bolts.
TORQUE: 1.8-2.2kg-m (13.0-18.1 ft-lbs)
CRANKSHAFT ASSEMBLY Check that the oil holes are not clogged .
Install the spark advancer shaft , 0 -ring and oil seal.
Install the bearing inserts.
Install the gears and assemble the upper and lower crankcases.
TORQUE : 2.0-2.5 kg-m (14.5-18.1ft-lbs)
10-8
a " D,F,J"
(;if\ HONDA ~ CB750