iVIOTORCYCLE
Triumph 650 & 750 Twins
cover. Clutch operating cam and gear
change ratchets (Fig, TM3-30) are
removed with the outer cover.
To remove the gear box inner cover
and gears (Fig. TM3-31), remove the
complete clutch assembly and unscrew
the output sprocket retaining nut.
Remove the two screws attaching inner
cover to transmission housing and
remove the inner cover complete with
cam plate, shift forks, gears and shafts.
To remove bearings (3, 12 & 36—Fig.
TM3-32), the respective housing should
be heated to approximately 100° C
(212° F). On all models except 3TA or
5TA, the needle bearing (12) should
project 0.073-0.078 inch into the
housing. Installation should be accomplished with a drift shown in Fig. TM333,
Bushing (5—Fig, TM3-32) should be
installed with oil groove toward gear
end of output shaft (4). All bushings
must be reamed after installation.
Refer to the following and Fig, TM3-32
for finished bushing specifications:
Bushing (5)—
diameter
0.752-0.753 in.
Clearance on shaft
(7)
0.0020-0,0035 in.
Protrusion
% in.
Bushing (12) for 3TA and 5TA models
only—
Diameter
0.6865-0.6885 in.
Bushing (20) for 3TA and 5TA models
only—
Diameter
0.689-0.690 in.
Bushing (18)—
diameter
0.689-0.690 in.
Clearance on shaft
(15)
0,0015-0.0030 in.
Free length of kick starter spring (22
—Fig. TM3-32) is Vz inch. Free length
of ratchet springs (3—Fig. TM3-30) is 1
1/16 inches. Free length of springs (8)
is 1% inch. Finished diameter of
bushing (6) should be 0.623-0.624 inch
and shaft (2) should have 0.001-0.003
inch clearance.
The gears and shafts should be assembled in the inner cover as removed.
Check operation before installing.
Shift forks (28 & 30—Fig. TM3-32)
must be installed correctly. To check,
shift the cam plate (25) to both extremes (first and fourth gears) and
check position of the guide rollers in
the cam plate grooves. If shift forks are
correctly installed, both rollers will
reach both ends of the grooves. If movement of either roller is incorrect, remove shift forks (28 & 30) and exchange places. NOTE: Shift forks are
not interchangeable. The rollers for
cam plate are offset.
TRIUMPH UNIT CONSTRUCTION
650 AND 750CC TWINS
Bonneville T120
Thunderbird 6T
Trophy TR6
649
71
82
2
Bonneville
Bonneville T140V
MODEL
T120V
Tiger TR7V
Displacement^-cc
649
744*
Bore—mm
71
76*
Stroke—mm
82
82
Number of cylinders
2
2
Ignition—
Spark plug type—Champion
N-4
N-4
N-3
Electrode gap—mm
0.5
0.5
0.635
Inch
0.020
0.020
0.025
Point gap—mm
0.35-0.40
0.35-0.40
0.35-0.40
Inch
0.014-0.016
0.014-0.016
0.014-0.016
Valve clearance (cold)
Intake-mm
0.05
0.04
0.20
Inch
0.002
0.002
0.008
Exhaust-mm
0.10
0.10
0.15
Inch
0.004
0.004
0.006
Electrical system voltage
** 12
12
12
Battery terminal grounded
Positive
Positive
Positive
Tire size-front .
t
3,25x19
3.25x19
Rear
t
4.00x18
4.00x18
Tire pressure—
Front—kg/cm2
1.68
1.68
1.68
Psi
24
24
24
Rear—kg/cm2
1.75
1.75
1.68
Psi ..
25
25
24
Rear chain free play
tt
tt
tt
Number of speeds
4
5
5
*Before serial numbers T140V XH22019 and TR7V AH24044, standard cylinder bore was 75mm
and displacement was 724cc,
**Early models are equipped with 6 volt electrical system.
tVarious tire sizes have been used including 3.25 x 18,3.50 x 18,4.00 x 18,3.25 x 19 and 3.50 x 19.
ttRear chain free play should be % inch (18mm) with weight on wheels or 1% inches (43mm) with
motorcycle on center stand.
Illustrations courtesy of Norton Triumph Corp.
MArNTENANCE
SPARK PLUGS. Recommended
spark plug for normal use is Champion
N58R for T120TT models. Champion
N-4 for other 650cc models; Champion
332
N-3 for all 750cc models. Spark plugs
are 14mm with % inch reach and heat
range may vary depending upon use.
Electrode gap should be 0.020 inch
(0,5mm) for all 650cc models; 0,025
inch (0,635mm) for 750cc models.
CARBURETOR. Amal Monobloc
and Concentric carburetors are used.
Bonneville T120 models use two carburetors, all others use one. Refer to
the following specification data:
SERVICE
Triumph 650 & 750 Twins
Mainjet (13)
330
Needle jet (11)
106T
Valve needle (5)
D
Throttle slide (3)
389/4
Pilotjet (6)
25
Clip (4) in top groove of needle (5).
T120 (Serial No. DU101-DU5824)
Refer to Fig. TM4-1
Model
376/
Mainjet (13)
240
Needle jet (11)
106
Valve needle (5)
C
Throttle slide (3)
376/3^2
Pilotjet (6)
25
Clip (4) in second groove from top of
needle (5).
Fig. TM4-1-Exploded view of typical Amal Monobloc carburetor used. Refer to Fig. TM4-2 for
view of Amal Concentric fioat carburetor.
1. Idle mixture need ie
2. Jet block screw
3. Throttle slide
4. Clip
5. Valve needle
6. Pilotjet
7. Idle speed stop screw
8. Fuel
filter
10. Jetholder
11. Needle jet
13. Mainjet
14. Throttle spring
15. Jet block
16 Float
17. Inlet valve
19, Primer
20. Choke valve
21. Cableguide
6T (Serial No. DUlOl and up)
Refer to Fig. TM4-1
Model
376/303
Mainjet (13)
230
Needle jet (11)
106
Valve needle (5)
C
Throttle slide (3)
376/4
Pilotjet (6)
25
Clip (4) in third groove from top of
needle (5).
TR6 (Serial No. DUlOl to DU5824)
Refer to Fig. TM4-1
Model
376/
Mainjet (13)
250
Needle jet (11)
106
Valve needle (5)
C
Throttle slide (3)
376/3V2
Pilotjet (6)
25
Clip (4) in third groove from top of
needle (5).
TR6 (Serial No. DU5825-DU44393)
Refer to Fig. TM4-1
Model
389/97
Mainjet (13)
310
Needle jet (11)
106
Valve needle (5)
D
Throttle slide (3)
389/3^2
Pilotjet (6)
25
Clip (4) in top groove of needle (5).
TR6 (Serial No. DU44394-DU66245)
Refer to Fig. TM4-1
Model
389/239
T120 (Serial No. DU5825-DU66245)
and T120R (Serial No. DU24875DU44393)
Refer to Fig. TM4-1
Model
389/203
Mainjet (13)
260
Needle jet (11)
106
Valve needle (5)
D
Throttle slide (3)
389/3
Pilotjet (6)
25
Clip (4) in third groove from top of
needle (5).
T120R (Serial No. DU44394DU66245) and T120TT (Serial No.
DU24875-DU66245)
Refer to Fig. TM4-1
Model
389/95
Mainjet (13)
330
Needle jet (11)
106
Valve needle (5)
D
Throttle slide (3)
389/3V2 or 389/4
Pilotjet (6)
25
Clip (4) in second groove from top of
needle (5).
Fig. TM4-2~Exploded view of Amai carburetor
with concentric float chamber.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Idle mixture needle
Float chamber
Throttle slide
Clip
Valve needle
Pilotjet
Idle sp>eed stop screw
Fuei filter
Baniobolt
Jet holder
11.
13.
14.
15.
16.
17.
18.
19.
20.
21.
Needle jet
Mainjet
Throttle spring
Cap
Float
Fuel inlet needle
Float pivot
Primer
Choke valve
Cable adjuster
Needle jet (11)
106
Throttle slide (3)
3
Clip (4) in second groove from top of
needle (5).
TR7V
Refer to Fig. TM4-2
Model
930/89
Mainjet (13)
280
Needle jet (11)
106
Throttle slide(3)
3^^
Clip (4) in second groove from top of
needle (5).
T120R (Serial No. 66246 and up)
Refer to Fig. TM4-2
Model—left
930/10
Right
930/9
Mainjet (13)
210 or 220
Needle jet (11)
0.106 or 0.107
Throttle slide (3)
2y2 or 3
On all models, idle mixture is adPilotjet (6)
20 justed at needle (1—Fig. TM4-1 or
Clip (4) in second groove from top of TM4-2). Idle speed is adjusted at screw
needle (5).
(7). On models with dual carburetors,
the carburetors must be synchronized
to open exactly the same amount by
T140V (Before Serial No.
adjusting the cable guides (21) at the
XH220019)
top of each carburetor. Idle mixture on
Refer to Fig. TM4-2
Model—left
930/88 carburetor is more easily adjusted after
right
930/87 disconnecting the spark plug wire from
Mainjet (13)
210 the other cylinder.
Needle jet (11)
106
Throttle slide (3)
3
IGNITION AND ELECTRICAL.
Clip (4) in second groove from top of Ignition breaker point gap should be
needle (5).
0.014-0.016 inch for all models. The
ignition breaker point cam and adT140V (After Serial No. XH22018)
vance weights are mounted on the
Refer to Fig. TM4-2
right end of the exhaust camshaft. IgModel—left
930/93 nition timing for the right cylinder is
right
930.92 adjusted by moving the breaker point
Mainjet (13)
190 base plate after removing the small
333
iVIOTORCYCLE
Triumph 650 & 750 Twins
1
Fig. TM4-4-The Ignition cam and advance assembly is mounted on the right end of the camshaft. Black and yellow wire goes to breaker
points (3) and black and white wire goes to
breaker points (4).
Fig. TM4-8-The peg (P) on the primary drive
sprocket should be at approximately 9 o'clock
position when the crankshaft Is at top dead
center (TDC).
TR6 and T120
(Serial No. DU101-DU5824)
Crankshaft degrees BTDC—
Static
11°
Full advance
39°
Advance range stamped on cam .. 14°
Piston position BTDC—
Static
0.038 inch
TR6 and T120 Models with Battery
Ignition (Serial No. DU5825 and up)
Static
15°
Full advance
39°
Advance range stamped on cam ., 12°
Piston position BTDC—
Static
0.068 inch
Fig. TM4-7-Coils (C) for models with AC (energy
transfer) Ignition are different than coils for bat•.
tery IgniUon models.
TR6 and T120 Models with Energy
Transfer Ignition (Serial No.
DU44395 and up)
Crankshaft degrees BTDC—
Static ,.,
, . . , 29°
Full advance
39°
Advance range stamped on cam , . , . 5°
Piston position BTDC—
Static
0.25 inch
round cover from the right side. It may
be necessary to vary the breaker point
gap on the second set of breaker points
in order to set ignition timing for the
left cylinder.
Ignition automatic advance range in TR7Vand T140V
camshaft degrees {V2 of crankshaft de- Crankshaft degrees BTDC—
Static
14°
grees) is stamped on the back of the
Full advance
,. 38°
breaker cam. Standard ignition timing
Advance range of cam
12°
is as follows:
Piston position BTDC—
Static
0.060 inch (1.5mm)
6T (Serial No. DU101.DU5824)
Crankshaft degrees BTDC—
Full advanced ignition timing should
Static
7°
Full advance
35° occur at 35° (crankshaft degrees) BTDC
Advance range stamped on cam .. 14° for all 6T models; 39° BTDC for all TR6
and T120 models; 38° BTDC for all
Piston position BTDC—
Static
0.015 inch TR7V and TRHOV models. Full advanced ignition timing can be checked
using a degree wheel mounted on the
6T (Serial No. DU5825-DU44394)
right end of exhaust camshaft and a
Crankshaft degrees BTDC—
Static
11° power timing light.
All models are equipped with an alFull advance
35°
Advance range stamped on cam ,, 12° ternator mounted at left end of crankshaft which charges the battery (if so
Piston position BTDC—
Static
0,038 inch equipped) via a full wave rectifier. On
334
later models, current is controlled by a
zener diode after being rectified. Clearance between alternator coil poles and
rotor should be 0.008 inch minimum all
the way around. Rotor retaining nut
should be torqued to 30 Ft.-Lbs. (4.1
kg-m) for all 650cc models; 40 Ft.-Lbs.
(5.5 kg-m) for all 750cc models. On all
models, stator mounting screws should
be torqued to 20 Ft,-Lbs. after correctly
centered over the rotor. Make certain
that stator wires do not rub on the primary chain. On models with AC (energy transfer) ignition, the alternator
rotor must be correctly timed to the
engine to provide the electrical current
for ignition. Models with energy
transfer ignition are equipped with
special high tension ignition coils
shown in Fig. TM4-7 located under the
fuel tank.
When assembling models with energy transfer ignition, observe the following: Install the primary drive
sprocket with the rotor locating peg at
approximately 9 o'clock position when
the crankshaft is at top dead center.
Refer to Fig. TM4-8. The rotor has
three holes marked "S", "M" and "R".
The "S" position should be used with
full advanced ignition timing at 37°
BTDC. The "M" position should be used
with 39° BTDC full advanced ignition
timing. The "R" position should be used
only if full advance ignition timing is
set at 41° BTDC,
NOTE: It is important that ignition
timing is correctly set in relation to the
rotor location. The current generated
when the breaker points open may be
insufficient to fire the spark plugs if
breaker points open too soon or too late.
If one set of breaker points is faulty,
both cylinders will be affected. If the
brown stop light wire is shorted, the
engine will not run.
VALVE SYSTEM. The valve clearance should be set with engine cold. On
650cc models, intake clearance should
be 0.002 inch (0.05mm) and exhaust
c l e a r a n c e should be 0.004 inch
(0.10mm), On 750cc models intake
c l e a r a n c e should be 0,008 inch
(0.20mm) and exhaust should be 0.006
inch (0.15mm). On all models, check
the clearance of one valve when the
similar valve for other cylinder is a
maximum opening, EXAMPLE: Clearance for the inlet valve for the right
cylinder should be set when the inlet
valve for the left cylinder is fully open.
LUBRICATION. On 650cc models,
i;he engine uses a dry sump lubrication
system. On models before serial
number DU24874, capacity is 6 pints
(2.8 liters); later models have capacity
of 7V4 pints (3,4 liters). Use SAE 40 oil
Triumph 650 & 750 Twins
SERVICE
6
Fig. TM4'9~Drawing of engine reservoir
lines typical of 650cc models.
F, Filter
P. Drain plug
1. Reservoir to pressure
pump hose
2. Oil manifold
3. Oil return hose
7
8
9
10 11
and
4, Rocker arm lubricant
line
5. Rear chain metering
needle
6 Hose to rear chain
7, Breather (vent) hose
8
9 12 13 10 14 11
Fig. TM4-10-The Oil pump is located at (P) and relief valve at (R). Exploded view of late type relief
1,
2,
3.
4.
Drive block
Pressure plunger
Scavenge plunger
Check valves
6
7.
8.
9.
Gasket
Valve body
Gasket
Relief valve plunger
10.
11.
12.
13.
Spring
Cap
Nut
Auxiliary spring
14,
15,
16,
17,
Rubber sleeve
Indicator shaft
Cover
"O"ring
Fig. TM4-11-Primary
chain
case shouid be filled to level
of plug (L) through top plug
(F). The chain tension adjuster is located inside hole
for drain plug (D).
TM4-9A). The oil should be drained,
filter (F) cleaned and reservoir should
be filled with new oil every 1000 miles.
Oil should be maintained between
D. Dipstick
2, Oil manifold
F. Filter
3, Oil return hose
marks on dip stick (D).
G, Gaskets
4, Rocker arm lubricant
On all models, installation of hoses
P. Drain plug
line
1, Reservoir to pressure
to and from the reservoir is important.
pump hose
Refer to Fig. TM4-9 and Fig. TM4-9A.
above 90 degrees F.; SAE 30 oil from 32 Oil is drawn from the reservoir to the
degrees F. to 90 degrees F. Oil level pressure pump through hose (1). The
should be maintained lV^ inches (4cm) scavenge pump delivers oil back to the
below filler cap opening of reservoir. reservoir from the engine through hose
Oil reservoir is located on right side (3). Oil pumped by the scavenge pump
under the seat. Remove filter (F—Fig. is also used to lubricate the rocker
TM4-9) from reservoir to drain oil and arms via hose (4). On some models, oil
clean filter. The oil should be drained, is metered by valve (5—Fig. TM4-9)
filters cleaned and reservoir should be and delivered to the rear chain through
hose (6). The engine will probably be
filled with new oil every 1500 miles.
On 750cc models, the engine is damaged because of lack of lubrication
equipped with a dry sump lubrication if hoses are attached incorrectly.
The oil pump is located on the right
system which contains 4.8 pints (2.27
liters). Use SAE 20W/50 multi vis- crankcase half under the timing gear
cosity motor oil. Oil is contained in the cover and is driven by an eccentric peg
frame tubes which forms the reservoir. on the nut retaining the timing gear to
Drain oil by removing plug (P—Fig. the inlet camshaft. Normal oil pressure
Fig. TM4-9A-Drawing of engine oil lines typical
of 750CC models. Frame tube Is reservoir.
is 20-25 psi at idle and 60-65 psi during
normal running. Refer to Fig. TM4-10
for exploded view of pump and relief
valve. On early models (bottom of Fig.
TM4-10), free length of relief valve
spring (10) should be 31/32 inch and
auxiliary spring (13) should be 9/32
inch long. On models after serial
number DU13375, relief valve spring
(10—top of Fig. TM4-10) should be 1
17/32 inches long.
On 650cc models, oil in primary
chain case should be drained every
1000 miles. The primary chain case
should be filled to level of plug (L—Fig,
TM4-11) with SAE 20 oil.
On 750cc models, oil in the primary
chain case is automatically maintained
at correct level by the engine lubricating system. Pour 150cc of engine oil
into the chain case before starting engine if chain case has been drained.
On all models, the gear box should be
drained every 6000 miles. The gear box
should be filled with EP 90 gear lubri335
MOTORCYCLE
Triumph 650 & 750 Twins
Fig. TM4-12-The gear box oil level plug is shown
at (M) and drain plug at (D). Filler plug is located
at top near ctutch cable.
Fig. TM4-13-Clatch spring tension can be adjusted as shown after removing the primary
chain cover. Refer to text.
cant until oil begins to flow from the
level plug hole. When checking gear
box oil level, it is necessary to fill with
oil until above the level pipe. Some oil
will be inside the pipe when level plug
is removed. Refer to Fig. TM4-12.
CLUTCH CONTROLS. To adjust
the clutch, remove the plug from the
side of primary chain case cover, loosen
the locknut and turn the adjusting
screw (A—Fig. TM4-11) in until resistance is felt. Back the adjusting screw
(A) out 1 turn and tighten the locknut.
Adjust the cable guide at hand lever
until cable has Vs inch free play.
If clutch slips with controls properly
adjusted, remove the primary chain
case cover and adjust the spring pressure. Initial setting is with adjusting
nuts flush with ends of studs. Each nut
must be adjusted to provide even
spring pressure. To check adjustment
of springs, shift transmission to neutral, disengage clutch and operate the
kick starter. Check the pressure plate
as it turns and make sure it does not
wobble. If one section of pressure plate
is higher than the rest, tum the spring
adjuster near the high spot in and recheck. To tum the adjusting nuts out,
it is necessary to hold the springs down
as shown in Fig. TM 4-13 to release the
locking lug on bottom of nut.
PRIMARY CHAIN. Tension of the
primary chain is adjusted by tuming
adjuster (T—Fig. TM4-11) after removing drain plug (D). Special hexagon headed screwdriver (part No.
336
Fig. TM4-14-Exptoded view of the front suspension used on early models (before serial number
DU5825). Refer to Fig. TM4-15 for later type.
1.
2.
3.
4.
5.
6.
7.
8.
9.
Killer plug
Tube
Spnntj
Bottom bushing
Washer
Bu.shingnut
Restriftor rcxl
Washer
Screw
10. Sleeve nut top
11. Oil .seal
12. Seal retainer sleeve
nut
13. Top bushing
14. Dampening sleeve
1.5. Lower tube
16. Drain plug
17. Guide tube
D496) should be used to tum adjuster
(T). The chain should have V2 inch free
play as measured through the filler
plug hole (F). Make certain that primary chain case is filled to level of plug
hole (L) with SAE 20 oil after adjustment is complete.
To remove the primary chain case
cover, remove the left exhaust pipe,
loosen the rear brake adjuster until the
brake pedal is clear of the primary
cover and remove the left foot rest.
Remove drain plug (D—Fig. TM4-11)
and allow primary chain case to drain.
Remove the two domed nuts and eight
attaching screws, then lift off the chain
cover. To remove the primary chain, it
is necessary to remove the alternator,
then remove the clutch, chain and
crankshaft sprocket together.
When assembling, tapered side of
spacer (5—Fig. TM4-24) must be installed toward the sprocket. Refer to
IGNITION AND ELECTRICAL paragraphs for installing alternator rotor
and stator. Make certain that alternator wires can not rub on primary
drive chain. Install chain tension adjuster and adjust the chain free play
after the chain case cover is installed.
SUSPENSION. Each front suspension unit contains 150cc of oil on all 6T,
TR6 and T120 models with internal
Fig. TM4-15-Exploded view of front suspension
used from serial number DC5825 to DU66245. On
some models, restrictor valve may be type
shown in Fig. TM4-1B. Refer to Fig. TM4-14 for
legend.
23
17
18
20
Fig. TM3'16-Vlew of restrictor valve used on
some models. Body (23) is attactted to lower
tube (15-Flg. TM4-15) with screw (9-Flg. TM4-1S)
and must be removed before disassembling.
1.
16.
17.
18.
19.
Filler plug
Rod
Pin
Cup
Oil restrictor
, .
20.
21.
22.
23.
Nut
Bushing
Restrictor cap
Restrictar body
SERVICE
Triumph 650 & 750 Twins
11
-13
Fig. TM4'17-Exploded view of front suspension
used on models from serial number DU66246.
Fig. TM4-18-Exploded view of front suspension
unit used on iate models.
1.
2.
3.
4.
5.
6.
7.
9.
1.
IS.
2.
3.
4.
5.
6.
7.
Filler plug
Tube
Spring
Bottom bushing
Washer
Bushing nut
Restrictor
Screw
11. Oilseal
12. Seal retainer sleeve
nut
13. Top bushing
14. Dampening sleeve
15. Lower tube
16. Drain plug
17. Snap ring
18. Shuttle valve
spring (Fig. TM4-14). On models with
external spring (Fig. TM4-15 or Fig.
TM4-17), each unit contains 190cc of
oil. The late type fork (Fig. TM4-18)
used on TR7V and T140V models
should contain 200cc of Automatic
Transmission Fluid (ATF). Recommended oil for earlier models is SAE 50
oil above 90°F. SAE 30 at temperatures
from 60°F. to 90°F., and SAE 20 oil
below 6O''F. Oil should be drained and
filled with correct type at least every
6000 miles. Oil is drained by removing
plugs at the bottom of fork lower
(sliding) tubes. Forks are filled through
the hole in top after removing plug (1—
Fig. TM4-14, Fig. TM4-15, Fig. TM4-17
orFig.TM4-18).
Disassembly and reassembly of late
forks is more easily accomplished using
the special tool shown in Fig. TM418A. The tool holds the damper tube
assembly (7—Fig. TM3-18) while removing or installing the Allew screw
(14). A 13/16 inch socket with a long
extension can be used to hold nut (4) in
a similar way if the special tool is not
available. Coat threads of spring seat
(lA) with "Permatex Super 300"; "Loctite Hydraulic Sealant" or equivalent
to prevent leakage.
Rear suspension units are sealed and
must be renewed if leaking or damaged.
Fork top bolt
Spring seat
Inner fork spring
Inner fork tube
Damper valve nut
Damper valve
Damper washer
Damper tube
assembly
8. Recoil spring
9. Inner fork tube end
plug
Seal for screw (15)
Dust cover
Oilseal
Outer fork tube
Oil drain plug
Damper tube holding
screw
10.
11.
12.
13.
14.
15.
REPAIRS
CYLINDER HEAD AND VALVES.
To remove the cylinder head, remove
the fuel tank, coils, top engine supports
(stays), rocker caps and rocker arm oil
line. On 650cc models, loosen all nine
cylinder head screws, remove the five
stud nuts and two screws attaching
rocker boxes to cylinder head and lift
off the rocker boxes. On 750cc models,
remove the attaching screws and stud
nuts, then remove the rocker hoses. On
all models, lift out the push rods and
mark for correct assembly in the same
location. Remove the exhaust pipes. On
650cc models, remove the five remaining cylinder head retaining
screws and lift the cylinder head off.
NOTE: The four cylinder head
screws which also attach the rocker
boxes are already removed. On 750cc
models, remove the ten cylinder head
retaining screws and stud nuts. NOTE:
Special threaded nuts are used at locations (3,4, 5 & 6—Fig. TM4-19A).
When the cylinder head is removed,
it is necessary to renew the push rod
tube oil seals. Refer to the following
specification data:
Rocker arm bore
(I.D.)
0.5002-0.5012 in.
Rocker shaft (O.D.) .. 0.4990-0.4995 in.
Fig. TM4-18A-A special tool is helpful for holding
the damper tube while removing screw.
Valve stem to guide clearance—
Inlet
0.0027-0.0032 in.
Exhaust
0.0032-0.0047 in.
Valve seat and face angle .. 45 degrees
Valve seat width
3/32 in.
Valve springs—type installed
6T Serial No. DUlOl and up
Inner-marked
Red Spot
Outer-marked
Red Spot
TR6 Serial No. DU101.DU24874
Inner-marked
White Spot
Outer-marked
White Spot
TR6 Serial No. DU24875-DU66245
Inner-marked
Red Spot
Outer-marked .
Red Spot
TR6 Serial No. DU66246 and up
Inner-marked
Red Spot
Outer-Marked
Green Spot
TR7V
Inner-marked
Red Spot
Outer-marked
Green Spot
T120 Serial No. DU101-DU24874
Inner-marked
White Spot
Outer-marked
White Spot
T120 Serial No. DU24875-DU66245
Inner-marked
Red Spot
Outer-marked
Red Spot
T120 Serial No. DU66246 and up
Inner-marked
Red Spot
Outer-marked
Green Spot
T140V
Inner-marked
Red Spot
Outer-marked
Green Spot
Valve spring—specifications
Inner-marked with red spot—
Free length
1 17/32 inches
Number of coils
7y4
337
MOTORCYCLE
Triumph 650 & 750 Twins
Fig. TM4-19-Cyiinder head retaining screws and
stud nuts should be tightened in sequence
shown for 650cc models. Refer to Fig. TM4-19A
for 750CC modeis.
Inner-marked with white spot—
Free length
1%
Number of coils
7
Outer-marked with red spot—
Free length
1% inches
Number of coils
5^2
Outer-marked with white spot—
Free length
2 1/32 inches
Number of coils
6V2
When reassembling, renew the push
rod tube oil seals and carefully position
the cylinder head making certain that
push rod tubes are correctly centered.
On 650cc models, start the cylinder
head screws (1, 6, 7, 8 & 9—Fig. TM419) and install push rods. On 750cc
models, install and tighten all ten cylinder head retaining nuts and screws
(Fig. TM4-19A), Turn the crankshaft
until both inlet push rods are at bottom
of travel, then install the rear rocker
box and rocker arms assembly, NOTE:
Be sure to install the three stud nuts on
bottom before installing the screws and
stud nuts on top. Turn the crankshaft
until both front (exhaust) push rods are
at bottom of travel, then install the
front rocker box and rocker arms assembly.
On 650cc models, the rocker arm
shaft nuts should be tightened to 22
Ft,-Lbs. (3.0 kg-m) torque. Rocker box
retaining screw and stud nuts which
are V4 inch size should be tightened to 5
Ft-Lbs. (0.7 kg-m) torque. The nine
cylinder head retaining screws and
stud nuts should be tightened in the
sequence shown in Fig. TM4-19, Final
torque for the 5/16 inch diameter
screws (Fig. TM 4-19) should be 15 Ft.Lbs. and 25 Ft.-Lbs. for the % inch
diameter screws.
On 750cc models, the 5/16 inch cylinder head retaining nuts (1 & 2—Fig.
TM4-19A) should be tightened to a
torque of 16 Ft.-Lbs. (2.21 kg-m).
Tighten the other cylinder head re338
Fig. TM4-19A-Cylinder head retaining screws
and stud nuts shouid be tightened in sequence
shown for 750cc models. Speciai nuts are used
at iocations (3, 4, 5 A 6) which accept rocker box
screws.
tain ing stud nuts and screws (% inch
size) to 18 Ft.-Lbs. (2.49 kg-m) torque.
Tighten cylinder head retaining hardware evenly and slowly. The V4 inch
size rocker box screws should be tightened to 5 Ft.-Lbs. (0.7 kg-m) torque and
the 5/16 inch screws to 10 Ft.-Lbs. (1.38
kg-m). Torque the rocker splindle
domed nuts to 22 Ft.-Lbs. (3.0 kg-m).
On all models, refer to the VALVE
SYSTEM paragraphs in the Maintenance section for setting valve clearance.
8.5:1
7.5 1
Fig. TM4-20-Triumph pistons can be identified
by measuring from center of piston pin bore. Pistons shown are for 650cc models.
A. 1.416-1.424 inches
B. 1.488-1.492 inches
C. 1.498-1.r)02 inches
D. 1.845-1.849 inches
A.
B.
C.
1.
Locking hole
Oil hole
Cutaway
Cam follower guide
block
2. "C'ring
3. Cam followers
PISTONS. RINGS AND CYLINDERS. Pistons and rings are available
in standard size and oversizes. Nominal bore size is 71mm (2.795 inches) Fig. TM4-21-On models after serial number
for 650cc models, 75mm (2.953 inches) DU24874, the exhaust cam followers are presfor early 750cc models, 76mm (2.992 sure lubricated and must be Installed with cut'
away areas (C) toward outside as shown,
inches) for late 750cc models.
Piston Skirt Clearance—
6T (Serial No. DUIOIT120 (Before Serial No. DU44394
except 11:1 Compression
DU5824)
0,0033-0.0043 inch
ratio)
0.0038-0.0048 inch
0.084-0,109mm
0.097-0.122mm
6T (Serial No, DU5825TR7V and T14DV (All 750cc
DU44393) , , , . 0.0016-0.0027 inch
models)
0.0036-0.0042 inch
0.041-0.069mm
0.091-0.107mm
TR6 (Serial No. DUIOIDU44393) , . , . 0.0033-0.0043 inch Maximum cylinder bore taper
or out of round
0,005 inch
0.084-0.109mm
0.127mm
TR6 (Serial No. DU44394 and up
Ring side clearance in grooves
except 11:1 Compression
ratio)
0.0046-0.0061 inch (650cc)—
Compression rings 0.001-0.003 inch
0.117-0.155mm
0.025-0.076mm
TR6 and T120 (Serial No. DU44394
Oil control
0.0005-0.0025 inch
and up with 11:1 Compression
ratio)
0.0070-0.0084 inch
0.013-0.064mm
0.178-0.213mm Ring side clearance in groove (750cc)—
T120TT (Before Serial No. DU44393
Compression
with 11:1 Compression
rings
0.0015-0.0035 inch
ratio)
0.0073-0.0083 inch
0.0038-0.089mm
0.185-0.211mm
Oil control
0.0015-0,0025 inch
T120 (Serial No. DU44394 and up
0.038-0.063mm
except 11:1 Compression
Ring end gap (650cc)—
ratio)
0.0046-0.0061 inch
All rings
0,010-0,014 inch
0.117-0.155mm
0.25-0.36mm
SERVICE
Triumph 650 & 750 Twins
Fig. TM4-22-On later 650cc
models, make certain hole
in cylinder base gasket is
over oil passages (A) in
crankcase and (B) in cylinder.
Fig. TM4-23-Make certain
that the two screws (S) are
removed when separating
crankcase halves.
Ring end gap (750cc)—
Compression rings 0.008-0.013 inch
0.20-0.33mm
Oil control
0.010-0.040 inch
0.025-1.02mm
When removing or installing the cylinder, a shock absorber mounting
rubber or similar rubber block should
be wedged between both sets of cam followers. If cam followers are not held in
position, they may fall into the crankcase. On models after serial number
DU24874, the exhaust cam followers
are pressure lubricated. If the exhaust
cam follower block is removed, make
certain that "0" ring (2—Fig. TM4-21)
is positioned around guide block and
locking hole (A) is aligned with lock
screw hole before pressing into cylinder. Exhaust cam followers (3)
should be installed with cut-away faces
(C) toward outside. Inlet cam follower
block on late models and both guide
blocks on earlier models should be similarly pressed into place; however,
these are not pressure lubricated and
do not have oil holes (B) or cut away
sections (C). On late models, make certain that the cylinder base gasket is
installed with hole in gasket over the
oil passage (A—Fig. TM4-22) in crankcase and oil passage (B) in cylinder.
When installing piston rings on all
models, make certain that side of the
two compression rings marked "TOP"
is toward top of piston. The cylinder
retaining nuts should be tightened to
35 Ft.-Lbs, torque.
CRANKSHAFT, CONNECTING
RODS AND CAMSHAFTS. To remove the crankshaft or connecting
rods, it is necessary to separate the
crankcase halves.
Remove the cylinder head, cylinder,
ignition base plate, ignition cam,
timing gear cover, oil pump and camshaft and crankshaft gears. NOTE: The
nuts attaching gear to camshaft are
left hand thread. Remove the clutch,
alternator (stator and rotor), primary
drive sprockets, primary drive chain,
gear box cover and transmission gears.
Remove engine from the frame and
remove the remaining screws and stud
nuts joining the crankcase halves.
NOTE: Two screws are located at (S—
Fig. TM4-23). Connecting rod crankpin
standard diameter is 1.6235-1.6240
inches (41.237-41.25mm). Bearing inserts are available in standard size as
well as undersizes.
1,
2,
3,
4,
29
12
11 26 25
Rotor retaining nut
Tab washer
Rotor
Primary drive
sprocket
5, Spacer
6, Rod bearing inserts
7, Oil tube
8, Plug
9, Screw (3 used)
10, Flywheel
11, Crankshaft gear
12, Nut
13, Bushing
14, Idler gear
15, Nut
16, Camshaft gear
18. Exhaust camshaft
19. Tachometer drive
20. Oil pump drive nut
21. Camshaft gear
22. Inlet camshaft
23. Spring
24. Rotary breather
valve
25. Ballbearing
26. Washer
27. Roller bearing
28. DoweKEnergy
transfer ignition
only)
29. Key (all except
energy transfer
ignition)
30. Oil seal
Fig. TM4-24-Exploded view of the crankshaft and camshafts. Nuts (15 B, 20) are left hand thread.
339
iVIOTORCYCLE
Triumph 650 & 750 Twins
3
19
2
1
7 6 5
20 18
Fig. Tf^4-27-Exploded view of the clutch assembly. Refer to Fig. TM3-2B for installation of rubber
cushions (11 & 12).
TM4-25-Camshaft timing marks must be 1. Spring nuts
correctiy aligned as described in text.
2. Springs
The crankshaft left (drive) side main
bearing should be of the roller type. On
models before serial number DU13375,
early type bearing can be changed to
the late roller type without changing
any other parts. On models between
serial number DU13375 and DU24874,
the late type roller bearing can be installed after installing the late type
crankshaft timing gear (11—Fig. TM424) and washer (26).
When assembling, the projecting
tabs on connecting rod bearing inserts
should be on same side. The connecting
rod nuts should be tightened to the
torque. Two types of connecting rod
nuts have been used. The early type
has a machined finish and should be
tightened to 28 Ft.-Lbs. torque (3.87
kg-m). The later, preferred nuts have a
dull grey finish for identification and
should be tightened to 22 Ft.-Lbs. (3.04
kg-m) torque. The nuts are self locking
but the manufacturer also suggested
using "Loctite" to prevent loosening.
The three flywheel retaining screws
(9—Fig. TM4-24) should be tightened
to 33 Ft.-Lbs. (4.6 kg-m) torque. Make
certain that the mating surfaces of
crankcase halves are clean and smooth.
Seal (30) should be installed from inside after removing the roller bearing
outer rod. Closed side of seal should be
toward main bearings (27). To remove
or install main bearings (25 & 27) from
crankcase bores, the crankcases should
be heated to approximately 100° C.
(212° F.).
When installing camshaft timing
gears, install gears on shafts using the
keyway nearest the correct timing
mark on gear. Several different gears
have been used, but marks are similar.
Early camshaft gears have only one
mark and are not interchangable. Late
gears have two marks. The "A" mark
(Fig. TM4-25) should be used for the
exhaust camshaft and the "B" mark for
the inlet camshaft. Install the idler
gear last making sure that marks are
aligned correctly. The slot on crankshaft gear should be between the two
340
3.
4.
5.
6.
7.
8.
9.
10.
11.
Spring cups
Adjusting screw
Pressure plate
Driven plate
long dashes on idler gear as shown at
(C). Align the correct dot (A) on exhaust camshaft gear with dot on idler
gear. On 6T models, align the correct
dot (B) on inlet camshaft gear with
short dash (S). On all other models.
12
11
12. Drive rubber cushion
(large)
13. Spider
14. Clutch hub
15. Inner cover
Friction disc
Nut
Washer
Outer cover
Rebound rubber
cushion (small)
13 14
16.
* 17.
18.
19.
20.
Spring screws
Clutch drum
Thrust washer
Rollers (20 used)
Drive hub
align inlet camshaft dot (B) with the
long dash (L) on idler gear.
CLUTCH. Clutch plates can be removed after removing the primary
chain case cover and the spring adjusting nuts (1—Fig. TM4-27). Six friction discs (7) and six driven plates (6)
are used on all models. To remove the
clutch drum and primary chain, it is
necessary to remove the alternator
rotor and stator, then use special
pullers to remove crankshaft primary
drive sprocket, clutch drum and primary chain. When removing the clutch
drum (17), the special puller which attaches to the drive hub (20) should be
used.
When assembling the shock absorber
cushions (11 & 12 Fig. TM4-28), use
soap to lubricate rubber cushions and
make certain that drive and rebound
cushions are on the correct sides of
spider (13) as shown. NOTE: Do not use
oil or grease to lubricate rubber cush-
Fig. TM4'2B-Ctutch cushions should be installad
as shown. Use soap if necessary whan installing,
but do not use oil or grease.
11. Rebound cushion
(sniall)
12. Drive cushion (large)
1. Gear shift pedal shaft
2. Clutch release plunger
3. Kick starter shaft
Fig. TM4'29^lew of gear box outer cover. Refer to Fig. TM4'30 for exploded view of tha oparating
assemblies.
SERVICE
Triumph 650 & 750 Twins
Fig. TM4-30-Exploded view of parts located in the gear box outer cover. Refer to Fig. TM4-29 for
assembled view.
1. Gear shift pedal shaft
2. Clutch release
plunger
3. Kick starter shaft
4. Guide plate
5. Ratchet pawls (2
used t
6. Ratchet springs (2
used*
7. Pedal return springs
H. Bushing
9. "C'ring
10. Gear shift pedal
11. Connecting link
(Before serial number
DU66246)
12. Clutch lever
13. Balls(3used—-Hiin.)
14. Camplate
15.
16.
17
18.
19.
20.
21.
Spring
Washer
Cotter pin
Kick starter gear
Return spring
Bushing
Kick starter pedal
Fig. TM4-32-Vlew of the gear
box Inner cover Installed.
Refer to text for removal
procedure.
Ftg. TM4-33-When removing
or Installing transmission
gears, be careful not to lose
thrust washer (10) or rotters
(2).
ions. "Loctite" should be used on
threads of the three screws attaching
outer cover (10—Fig. TM4-27) to the
huh (14). Install spacer (5—Fig. TM424) with tapered side toward main
hearing. Position the crankshaft primary drive sprocket, chain and clutch
drum (17—Fig. TM4-27) on shafts at
the same time. Washer (9) should he
installed with cupped side out toward
nut. On models after serial numher
DU48144, nut (8) is self locking. On
earlier models, lock washer should he
installed hetween washer (9) and nut
(8) with the long tah engaging hole in
spider (13). On all models, nut (8)
should he tightened to 50 Ft.-Lhs.
(6.9kg-m) torque. On early models,
with lock washer, washer should be
bent around nut after tightening. Refer
to ignition and electrical section when
installing the alternator rotor and
stator. Refer to the primary drive chain
paragraphs for adjusting chain tension.
FOUR SPEED GEAR BOX. To
remove the gear box outer cover, remove the exhaust pipe and foot rest
from the right side. Loosen clutch cable
adjuster and disconnect cable from the
actuating spoke. Drain gear hox and
engage fourth gear. Remove the two
nuts and four screws attaching outer
cover, then remove the outer cover.
Clutch operating cam, kick starter and
gear change ratchet (Fig. TM4-29), are
removed with the outer cover.
To remove the inner cover, bend the
tah washer back and remove nut (5—
Fig. TM4-32), then lift off the kick
starter ratchet assembly. Unbolt and
remove the right rear engine mounting
plate. Remove nut (4) and withdraw
the detent plunger and spring. Remove
the primary chain cover, alternator
assembly, primary chain, crankshaft
sprocket and the complete clutch assembly. On models before serial
number DU24875, disconnect the
speedometer cable. Remove the three
screws (1, 2 & 3) and remove the inner
cover. Remove the shift fork rail then
lift out the transmission gears and
shafts as shown in Fig. TM4-33. The
transmission output shaft and fourth
gear (4—Fig. TM4-34) can be bumped
out of bearing after the output sprocket
(28) is removed.
If needle bearings (11 or 12) are renewed, bearings should be installed as
shown in Fig. TM4-35 using a special
drift. Bearing (12—Fig. TM4-34) is
closed on outside end, bearing (11) is
open. When removing and installing
bearings (11, 12, 14 & 25), the appropriate case should be heated to 100° C
(212° F.). Oil seal (27) should be installed with open side toward the
bearing (25) and against snap ring (26).
341
MOTORCYCLE
Triumph 650 & 750 Twins
25
26 27
29 30
Fig. TM4-37'The kick starter return spring
should be installed on spline shown,
10
13 6
10 12
Fig. TM4-34-Exploded view of four speed transmission assembly. Refer to Fig. TM4-33 for assembled view.
2.
3,
4,
5.
6
7.
Input shuft
(mainshafl)arvd first
gear
Sliding gear (2nd)
Sliding gear (3rd)
Output shaft and
fourth gear
Bushing
First gear
Sliding gear (2nd)
8. SlidinggearOrd)
9 Counter shaa
(layshafl) and drive
gear
10. Thrust washers
11. Needle bearing
(open)
12. Needle bearing
(closed end)
Bushing (5) should be pressed into
shaft (4) with oil groove toward teeth
on shaft. Bushing should protrude
7/16-inch and must be reamed after
installation to provide 0.0032-0.0047
inch clearance on input shaft (1). First
gear bushing (13) should have 0.00250.0045 inch clearance on counter shaft
(9).
When assembling, observe the following: Install the cam plate (C—Fig.
TM4-36) and detent plunger (D), spring
and nut (N), Turn the camplate until
the notch between second and third
gears engages detent plunger as shown
in Fig. TM4-36. Use grease to stick the
13. First gear bushing
14. Ball bearing
15.
16.
17.
18.
19.
20.
21.
Snap ring
Clutch rod bushing
Clutch rod
Washer
Sleeve
Ratchet spring
Kick starter gear
22.
23.
24.
25.
26.
27. Oil seal
28 Output sprocket
29. Lock washer
30. Nut
thrust washer (10) in position with
grooved side out as shown. Stick the
rollers (2—Fig. TM4-33) onto forks
with grease. Slide the assembled shafts
into housing while carefully sliding
gears as required to align rollers (2)
with grooves in cam plate (C). NOTE:
Be careful not to move the camplate
when assembling. With parts correctly
positioned in housing, slide the shift
rail through shift forks with shouldered end (S) toward inside. Use grease
to stick thrust washer (10) around
bearing (11—Fig. TM4-34) in the inner
cover with the grooved side toward
gear (6). Coat mating surfaces of inner
Fig. TM4-36-When assembllng four speed transmission, detent plunger (D)
should engage notch between 2nd and 3rd gears
and the camptate (C) as
shown.
////////////A
Fig. TM4-3S-tf needle bearings (11 and 12-Fig.
TM4-34) are removed, bearings should be Installed using a special drift. The bearings should
project 0,073-0.076 inch (C) Into the housing.
A. VA inches
342
B. U/16inch
C. 0.073-0.078 inch
Ratchet
Tab washer
Nut
Output shaft bearing
Snap ring
cover and gear case with sealer, align
the center tooth of the gear selector
quadrant with center line of transmission input shaft as shown at (A—Fig.
TM4-32) and install the inner cover.
Install the gear box outer cover temporarily and check for correct shifting.
NOTE: If gears can not be shifted correctly, remove the covers and check
position of camplate (C—Fig. TM4-36)
and quadrant (A—Fig. TM4-32). Install the kickstarter ratchet assembly
(18 through 23—Fig. TM4-34) over end
of shaft and tighten nut (24) 45 Ft.-Lbs.
torque. NOTE: Sleeve (19) may be
crushed if nut (24) is over tightened.
When assembling the gear box outer
cover, refer to Figs. TM4-29 and TM430. The kick starter return spring
should be installed with inner end of
spring over the spline shown at (L—
Fig. TM4-37). Refer to appropriate
paragraphs when assembling the
clutch and the alternator assemblies.
The table on the following page lists
details of various transmission parts
used in four speed transmission. Refer
to Figs. TM4-45, TM4-46, TM4-47,
TM4-48 and TM4-49 for explanation of
stepped and non-stepped (parallel)
shafts; shaved and non-shaft gears;
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SERVICE
Triumph 650 & 750 Twins
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iVIOTORCYCLE
Triumph 650 & 750 Twins
0-938& in. i
0-0980 inj
LAYSHAFT 3rd Gf AR
Fig. TM4-45-Vlews of four
speed transmission input
shafts (mainshafts} showing
differences between non-
NON-STEPPED MAINSHAFT
STEPPED MAINSHAFT
8IMALI 8ORE
1-1230 in.
1-12t5 in.
stepped and stepped types.
Fig. TM4-48~Cross section drawing of mainshaft
second gear with bore diameters for iarge bore
and smaii bore types.
0 9945tn.
0 9940 in.
0 9985 in. ^
0 9980 in.
NON «* STEPPED tAYSHAFT
STEPPED
tAYSHAFT
UNSHAVED
OEAR
small and large splined gears. Also
listed are the dates when used in original production. Some of the improvements incorporated in later production
can be installed in earlier transmissions; however, it is extremely important to select the correct combination
to ensure proper operation. Small bore
gears should never be installed on a
non-stepped shaft and large bore gears
should never be used on a stepped
344
MAMSHAFT 2nd PC AH
Fig. TM4-46-Views of four
speed countershafts (layshafts) showing differences
between stepped and nonstepped types.
Fig. TM4'49-Cross section drawing of layshaft
third gear with bore diameters for targe bore
and small bore types.
FIVE SPEED GEAR BOX. To
remove the gear box outer cover, remove right side exhaust pipe and foot
rest. Loosen the clutch cable adjuster
and disconnect cable at the hand lever.
Remove plug from cover and release
the cable from actuating arm. Disconnect cable and housing from gearbox
outer cover. Drain gear box and engage
fifth gear. Remove the two nuts and
four screws that attach cover, then
depress kickstarter slightly and remove cover. The clutch operating cam,
Fig. TM4-47''Views showing
differences between unkick starter and gear change ratchet
shaved and shaved gears.
are removed with cover.
To remove the inner cover, unbolt
and remove the right rear engine
moimting plate. Bend tangs of lock
washer down and remove nut (24—Fig.
TM4-52). Remove the three screws (3)
and remove cover from dowels.
Remainder of disassembly will deOEAR
pend upon work done. The complete
clutch assembly must be removed beshaft. Mainshafts have two different fore input shaft (1—Fig. TM4-50) can
types of threads (C.E.L or U.N.F.). Be be removed. The transmission output
sure that the nuts and spacers are cor- sprocket (28) must be removed before
rect for the shaft used as well as the output shaft (4) can be removed.
The gearbox or cover should be
gears used. Installing late mainshaft
high gears in early transmission may heated to approximately 100°C. when
necessitate installing later plate and removing or installing bearings. Refer
seal at rear of clutch. The gearbox to Fig. TM4-35 for installing countercasting must be modified to change shaft (layshaft) needle bearings. The
layshaft (countershaft) from plain bronze thrust washers on the countershaft should be positioned with grooved
bushing to needle roller type.
SERVICE
Triumph 650 & 750 Twins
28 29 30
16
1
17
V
Fig. TMA-St-Drawing of transmission showing
positions of shift cam and shift fori(s in neutral.
24
23 22 21 20 19 18
11 12 8B
6
15 14
8
7B
9
7
3B 3
2
10
Fig. TM4-50-Expioded view of five speed transmission gears and associated parts.
1. Input shaft
(mainshafl)
Fourth gear
Third gear
Bushing
Output shafl and
fifth gear
5. Needle roller
bearings
5S. Oilseal
2.
3.
3B.
4.
6.
6B,
7.
8.
9.
10.
First gear
Bushing
Second gear
First and second gear
Third gear
Countershaft
(layshaft) with fourth
gear and drive gear
11. First gear drive dog
surfaces toward gear on shaft (10—Fig.
TM4-50) and first gear drive dog (11).
Assemble transmission gears, shafts,
shift forks and shift cam with parts in
12.
14.
15.
16.
17.
18.
19.
20.
21.
Snap ring
Ballbearing
Snap ring
Clutch rod bushing
Clutch rod
Washer
Sleeve
Ratchet spring
Kick starter gear
22.
23.
24.
25.
26.
27.
28.
29.
30.
Ratchet
Tab washer
Nut
Output shaft roller
bearing
Snap ring
Oilseal
Output sprocket
Lock washer
Nut
first gear. Install the cover with the top
of the second tooth on quadrant aligned
with center of foot change spindle bore
as shown at (A—Fig. TM4-52).
Fig. TM4-52-Drawing of inner cover showing the
three screws (3) which attach cover.
Fig. TM4-53-The fourth speed gear and the drive
gear are pressed onto the countershaft (iayshaft). Distance (D) must be 0.653-0.655 inch
(t6.58-16.64mm} and clearance between gears
shouid be at feast 0.007 inch (0.18mm).
345
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