Workshop Manual - Supplementary Pages - Workshop Manual for Unit Construction 650 cc Twins - 1964/5 to 1966

Oct 23, 2026

Upload by Jacob

Supplementary service pages compiled to provide workshop, fitter, technical staff, and individual owners with essential maintenance and repair information for Triumph 650 c.c. unit construction twin-cylinder motorcycle models. The manual organizes general data into ready-reference format and divides technical coverage by major assemblies, following strip down, examination, and rebuilding sequence order. It includes guidance on engine and frame number locations and correspondence requirements, plus lubrication system details and core engine specifications.

LanguageEnglish

CategoryResearch & Report

FormatPDF

Pages100

Reading Time4 h 12 min

AccessFree to download

Introduction

Engine and Frame Numbers

General Data

Also Alternative Fitments for TR6 and T120 Sports Models

General Data Model 6T—Thunderbird - Lubrication System

Oil Pressure Release Valve

Oil Pressure

Engine - Basic Details

Crankshaft

Connecting Rods

Gudgeon Pin

Small End Bush

# SUPPLEMENTARY PAGES FOR WORKSHOP MANUAL FOR UNIT CONSTRUCTION650 cc TWINS 6T THUNDERBIRDTR6 TROPHYT120 BONNEVILLE T120 (UPDATING 1964/5 MANUALS TO 1966 CONDITION) Copyright by ## INTRODUCTION THIS manual has been compiled and prepared to provide the necessary service information for workshop,fitter,technical staffand individual owner,wishing to carry out basic maintenance and repair work on theTRIUMPH 650 c.c.series of unit construction twin cylinder models. GENERAL DATA for all models within the above range is provided in ready reference form,and a separatesection covering Service Tools is fully illustrated at the end of this manual. The manual is divided into sections dealing with major assemblies,throughout the machine,each section sub-divided into sequence order corresponding to normal operations of strip down,examination and rebuildingprocedure. ## ENGINE AND FRAME NUMBERS NOTE.The engine number is located on the left hand side of the engine immediately below the cylinderbarrel to crankcase flange.The engine type is incorporated as a prefix to the engine number. The frame number of the machine is stamped on the left side of the machine,on the frame headlug,beneath thetop fork lug,and forward of the fuel tank. Both the engine and frame numbers should be given IN FULL in any correspondence relating to the machineeither with your local Triumph Dealer or the Distributor. EASTERN U.S.A.DISTRIBUTORS WESTERN U.S.A DISTRIBUTORS JOHNSON MOTORS INC.P.O.BOX 457,PASADENA,CALIFORNIA 91102, 267 WEST COLORADO BLVD.Cables:"Jomo". THE TRIUMPH CORPORATION, P.O.BOX 6790,TOWSON,BALTIMORE 4,MARYLAND 21204.Cables:Triumph Baltimore. O C 〇〇 U C O O 0 ## GENERAL DATA 6T ThunderbirdTR6 TrophyT120 Bonneville ## Also Alternative Fitments for TR6 and T120 Sports Models Note:—Throughout this Section,read All Models as for 6T Thunderbird,unlessotherwise detailed under the particular Model Modifications for 1966 Models (Engine No.DU.24875)are listed on pages GD19&20 ## GENERAL DATAMODEL 6T—THUNDERBIRDLUBRICATION SYSTEM | OIL PUMP | | | | | | | | | | | | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | Body material | | …… | | | … | … | …… | . | …
… | Brass
·3748/-3753 in. | | | …
…
Bore diameter:Feed ... | | | … | … | | | … | … | … | ·4372/·4377 in. | | | …
Scavenge | | … | … | … | …… | .….
.. | … | .. | … | ·3744/-3747 in. | | | …
Plunger diameter:Feed
Scavenge… … | | …… | …… | …… | … | ... | …… | … | …… | ·4369-4372 in. | | | Valve spring length | | … | … | … | …… | ...
.. | … | ...
... | … | in.
in. | | | | | | | | | | | | | | | | Ball diameter … | | | | … | … | ... | … | ... | … | ·497|·498 in. | | | Aluminium crosshead width …
Working clearance in plunger heads | | …
… | …
… | | … | | … | | … | ·0015/-0045 in. | | ### OIL PRESSURE RELEASE VALVE ·5605/-5610 in.Piston diameter .…·001/·002 in.Working clearance601b./sq.in.(4-22 kg./sq.cm.)Pressure release operatesIndicator spring length(Free)孽in.Release spring length (Free) ……… ………… …………… ………… … ………… ………… … …… …… … ### OIL PRESSURE Normal running ...6 ·Idling…….65/80 Ib./sq.in..20/25 Ib./sq.in. … ENGINE | BASIC DETAILS | | | | | | | | | | | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | Bore and stroke
… | | …… | …… | . | …… | …… | …… | …… | …
… | 71×82 mm.
2·795×3·228 in. | | …
Bore and stroke …
… | | | | | … | … | … | … | | 649 c.c.(40 cu.in.) | | …
…
Cubic capacity …
Compression ratio
… | | ……… | ……… | ……… | …… | …… | …… | …… | …
…
… | 7·5:1
50 c.c.(3·05 cu.in.) | | Capacity of co

FAQs

Where are the engine and frame numbers located on the machine?

The engine number is on the left side of the engine immediately below the cylinder barrel to crankcase flange, with the engine type as a prefix. The frame number is stamped on the left side of the machine on the frame head lug, beneath the top fork lug, and forward of the fuel tank.

What information should be provided in correspondence about the machine?

Both the engine and frame numbers should be given in full in any correspondence, including with the local Triumph Dealer or the distributor.

What does the supplement provide for the TRIUMPH 650 c.c. unit construction twin models?

It provides necessary service information for basic maintenance and repair, with general data in ready reference form and a lubrication system section plus core engine specifications, organized by major assemblies and the normal operational sequence of strip down, examination, and rebuilding.

Oct 23, 2026

Upload by Jacob