Triumph 1978 User guide

L
O\N ERS
ANDBOOK
FOR
197 MODEL
,----NNEVI E 715D
140
PART NO. 99-7007
U. .A. EDITION
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Specialthanksto
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T
OWNER'S HANDBOOK
FOR
BO EVILLE 750
UNIT CONSTRUCTION TWIN
1978
MODEL
© Copyright
AI! rights reserved. No part of this publication
may be reproduced without permission.
Meriden Motorcycles Ltd., Meriden Works, Allesley, Covemry, England.
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INDEX
Page
Air filter......... ....... .. .. .......... ... .. .......... . .. .... ..... ....... .... .............. .. ........ 33
Brakes............ ... .. ............... ... . .. ................... ..... ................... .. ........... 26
8rake adjustment . .. ... . .. .. .. ... ... ... .......... .................. . ... .............. .. ...... 15
Carburetor........... ... ....... .... .. ................... ......................... .... ....... .. ... . 32
Chain adjustment......................................... ... .. ................ .... .... ....... 19
Cleaning your motorcycle........ ... ....... .... .. ....... ..... ..... ................. .. ..... 30
Controls .. .... ... ...... ... .. ... .. ....... .. ............................. .... .... .. . ... .... .. ......... 10
Electrical equipment.... ... .... .. ............. .... ... .... ......... ... .................. .... . 34
Front forks............... .. ............................................ .. ......................... 22
General description ... ....................................... .. ............................ .. 9
Guarantee arrangements ...................... .. ................ ... .............. ........ 4
Ig ni tion timing.................... .. ................... .. ................. ..... .... .............. 28
Lubrication .... ... ...................... ... . .. ................ ..... ................... .. ..... 41,42
Oil changing... .. ...... .. ... .. .. .. .......... ... ........................ .. .. .......... .. .. .... .... 30
Rear suspension ...... .. ..... ... ~ ...: .. ~ ... .. :....................... .. ... ................... 23
Routine maintenance .... ~~' . ~~1 ;. ... ~.r ~' .~ .. ~~ ; ~.. .......... ..... . . ..... .. ....... ....... 40
Breaking-in ...... .. ..... ... ..... .. ........ .. ............:.............................. .. ... ...... 13
Sparking plug ........... .. ........ .. .. ... . ... ........ ............ .. . .... .................. .. .... 29
Starting....... .. ..... .. ......... ... .. ... ................................................ .. .......... 12
~
Tires . .. ............ ... ................... ... ................... .... ................. .... ........ .... . 26
,
Useful data......................... ... ...... .... . .. .............. ... .................... .. . 6, 7, 8
Valve adjustment................. .. ......... ... ....... .... ....... ... .. ... ..... ............... 13
Wheels ... ....................... .. .. ..... .. .................................................... .... 24
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ILLUSTRATION INDEX
Fig. Page
1 Control layout . .. ......... .. ...... .. ........ .. .. ....... .. .... ... ... "'. .. .. .. ..... ... .. ... 11
2 To adjust valve operating mechanism ........ .. ......... .... .. ...... .. .. ... 14
3 Showing arrangement for bleeding the front brake.... ... .. . .. .. .. ... 16
4 Showing the brake reservoir fluid level and cap ............. .. .. ...... 17
5 To adjust rear brake.. ... ..... .... ........................... .. ................. .. ... 18
6 To adjust the primary chain...... ... ..... .. .. ...... ... ........ .. ........ .. ....... 20
7 To adjust the rear suspension springs ............ .. ........ ... ... ......... 23
8 Contact breaker................. .. ............... ... ........ ... ...... ... ........... .... 28
9 Gearbox drain and level plugs......... .. . .... ................ ... .... ... ..... ... 31
10 Amal concentric carburetor......... .. ..... ... .. .......... .. ... ....... ... ..... .. .. ~13
11 To secure the rectifier................... .. ........... .. .................. .. ........ 37'
12 Zener diode, model ZD71S.......... .. . .. ... ......... .. ..... .. .............. .. ... 38
13 Wiring diagram.... .. ....... .. ....... ... ....................... .. ............ .... .. ..... 39
14 Lubrication pOints ..... ... ... ............... .. ..... .. ....... .. . .... ............ .. ... ... 41
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INTRODUCTION
The Ow ner's Handbook in cludes all the information that the majority of
owners will require.
If you require more information for major repairs
there is available a Workshop Manual but this is intended for those
having basic mechnical knowledge and workshop facilities.To obtain the
Workshop Manual order from your local Triumph dealer or distributor as
we
do not supply parts or service literature direct from the factory to
individual customers.
Where specialised advice is required beyond the ability of the dealer,
then you should write to your distributor who will act on our behalf. Unless
the full engine number is quoted it is often difficult to identify the type of
motorcycle and give a helpful reply. Any information which may have a
bearing on the subject should be included, particularly details of any
additions or alterations to the standard equipment.
Where a guarantee claim is involved, consul your dealer or distributor
who may
be able to provide a replacement to enable yo ur motorcycle to
be
use d whilst the defective pa rt is returned to hi s distributor. Guarantee
claims in respect of prop
ri etary components should be forwarded by your
dealer to his distributor.
The terms of the U.S. Triumph guarantee can be obtained from your
dealer.
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Bonneville 750 T140-E
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USEFUL DATA
MOTOR
Bore and Stroke -mm ....................................... .. .. .. . ..
Bore and Stroke - in ...................... ... ...................... .. ..
Capacity -cu. in .. ... ................ ... .. .. ..... .. ......................
Compression Ratio.
.. .. .. .................. ... .. .................. .. ...,
Tappet Clearance, Inlet and Exhaust -Cold mm.......
.. .
Tappet Clearance, Inlet and Exhaust -Cold
in ......... ..
Valve timing checked at nil tappet clearance
76 x
82
2.993 x 3.228
45
7.9:1
0.203,0.15
o OOB, 0.006
Valve lift: Inlet opens 0.190ins (4.83mm) at T.D.C.
Exhaust closes 0.130ins (3.27mm) at T.O.C.
IGNITION -Timing (Before top centre)
Crankshaft position (Fully advanced) .......................... 380
Contact Breaker Gap - mm .. ... .. .... ............................. 0.35 -0.40
Contact Breaker Gap -in........ .. ... ....... .. ...................... 0.014 - 0.016
SPARK PLUGS
Type .... .. .. .. .. .................... .. ......................... ... .. .... .. ... .. . Champion N3
Point Gap - mm .. ..... .... ................. .. ... . .... ....... .. ......... .. 0.635
Point Gap -in
.. ..... .. ....... .. .. .. ... . .. ........ ... .. ... .. .. ........... .. 0.025
CAPACITIES
Gas Tank... .. .......................... .. .. ..... .. ...... .... ........... .. . .. 2V2 U. S. galls
Oil Reservoir
... ... ......................... ... .... . ... .. .. .. ...... ... ... ... 4.B U.S. pints
Gearbox - c. c........... .. .. ..... .. .................. .. ........... ... . ... .. 500
Primary chaincase (Initial fill) - e.c......
... .. ... ................ 150
Front forks (each leg) - c.c. .. .. ............. .. .. ............... .. .. 190
Front brake hydraulic system - C. c. ...... .. .... .. .............. Ap prox 189
(1fJ imperial pint)
CARBURETORS
Amal Type....... .................................. .. ........... .. ....... .. " R2930/1, L2930/2
Main Jet .. ..... .. .................... .. ........................... ... .. .... .. 200
Needle Jet......... ... .. .. ....... .. .. . .. . ... .. .. . ... ......................... .105 (2928/030)
Needle Type....... .. .. .. ...... ............................................. 2C3
Needle Position..............
.. . .. ....................... ... .. .. ... ....... 2
Throttle Valve Cutaway..........
... ................................ 3
Pilot Jet ... ............. .................................. .................. ... 25
Starter Jet....... .. . .. . .. .................................... .. ............... 50
Primary Air Jet.. .......................................................... 3.5
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FUEL
Octane Rating (minimum) ... ............... .. . .. .. ........... ... .... 97
Premium grade
Hydr aulic front brake fluid . ... ..... .. ........ ... .. .. .. .. .. ........... To conform with
SPROCKETS
DOT 3 Federal
motor vehic
le
standards 116
Ge arbox.................. ... .. .. .. .. ....... ...... .. ..... ... ... ......... ... .. 20T
Rear Whe el .. ... ... .... .. ... .. .. . .. ... .... .. .. ....... .. ............. .. .. .. . 47T
CHAINS
Primary - 3/
a
in pitch x V4in wide, Triplex, li nks ... .. .... .. 84
Secondary - o/ai n pitch x 3/sin wide, links .. .. ... .. .. .. ...... 106
GEAR RATIOS
5th Top ..... .. ................. .. ......... . .. ....... .. . .. ............ .. .. .. .. .. 4.70
4th Fourth...... .. .. ... ....,...... .. .................. .. ......... .. .. ......... 5.59
3rd Third
... .. .. .. .. .. .... .. ............... .. .. . .. ......... ... .. ... .. ..... .. ... 6.58
2nd Second .......
.. ... .......................................... ... .. .. .... 8.63
1st Bottom..
.. .. .. ... .. .................. .... .... .. ... ........... .. .. ........ 12.25
Engine r.p.m. @ 10 m.p.h.
in top gear .. .. .... .. .. .. .. ...... .. 627
TIRE SIZE
Front. .. ............ ... .............. .. .. ................ .. .. ..... .... .......... 4.10 x 19
R
ear.. .................. .. .. .. .... .. .. .. ............ .. .............. .. . .. ...... 4.10 x 18
TIRE PRESSURES
Front /b /sq . in..... .. ...... .. ...... .. ....... .. ........ .. ... .... .... .. .. . .. . 28
Rear
Ib/ sq. in ..... .. ..... .. . .. . .. ... .... .. ....... .. ... .'.. . .. . ... .... .. .. ... 32
BUL BS
Headlight 12v 45/40W Prefocus ............. ... .... ....... ... .. .
Parking light 12v 6W M.C.C........ ... .. ..... .. ........ .. ........ ..
Stop/Tail light 12v 5/21 W (offset pin) ........ .. .... .. .. .... . ..
Speedometer 12v 3W M.E.S... .. ....... .. .................... ... ..
Ignition warning light 12v 2W .. ..... ... .. ..... .. .... .. ........ ... ..
Hi-beam warning light 12v 2W ......................... .. .. . .. .. ..
Indicator warning light 12v 2W ......... ... ...... .. .. ............ ..
Direction indicators 12v 21 W .. ........ .. ........... .. ...... ... .. ..
Fuse rating (Amperes).............. .. ... ......... ....... .. ......... . ..
7
Lucas 410
Lucas 989
Lucas 380
Lucas 987
Lucas
281
Lucas 281
Lucas 281
Lucas 382
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OVERALL DIMENSIONS
Length - in . ......... .. ............ .. ... .. .. .... .. ... .................. . .. 87.5
Width - in....... ..............
.. ......"...... .. .... .. ....................... 33.0
Seat height -
in . " .. ..... ... .. .... .. .... ..... ...... .. ....... ... .. .... ... 31.0
Weight - lb . (unladen) .. .. .. .............. .. . .. .. " ..... .. .......... ". 395
..:..
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