1966 Triumph TR6

1966 TRIUMPH TR6 BY THE NUMBERS
For the 1966 model year, the model lineup were TR6, TR6R, TR6SR, TR6SS, TR6C & TR6SC, all called "Trophy". Engine & Frame Numbers ran from DU24876 to DU43161, with build dates running from August 6, 1965 to July 8, 1966. The TR6C was essentially a standard 1966 Triuymph TR6 with wide-ratio gearbox, slimmer 2.3-gallon tank & Dunlop Trials Universal tires (tyres). The TR6SC was the same as the TR6C except for standard gear ratios, alloy mudguards (fenders) & a silenced exhaust. The TR6SR was basically a standard 1966 Triumph TR6 but with raised handlbars & a smaller capacity fuel tank. The prices new were around $1,200 USD.

ENGINE MODS
Shorter "Red Spot" valve springs were installed with thicker bottom cups to ensure better valve control with less spring surge. A new central flywheel, lighter by 2-1/2 pounds, was fitted to the crankshaft, while maintaining the 85% balance factor. Crankshaft end float (lateral movement) control now reverted back to the timing side main bearing (having been moved for one year only, in 1965, to the drive side). This was accomplished by a clamping washer that was interposed between the timing pinion (gear) & the main bearing inner spool. And on a drive side, a heavier, load carrying single lipped roller bearing (#RM11L) replaced the old ball bearing.

BETTER OILING
Oil was now pressure-fed to the exhaust cam followers through drillways in the crankcase, barrels & exhaust tappet block. Starting with engine #DU42399 a dowel was placed at the joint between the crankcase & barrels to stem oil seepage. The new tappet blocks were made to fit new, redesigned pushrod tubes with better sealing top & bottom.

HOT ROD
Starting with engine #DU42251, the 3/4" radius cam follwers (tappets) were replaced by the now-famous "R-type" tappets of 1-1/8" radius. The intake (inlet) valves were also increased in head diameter from 1-7/16" to 1-19/32", and the exhaust valves were enlarged to 1-7/16", just like the Triumph Bonneville T120.
GEARBOX MODS
Starting with the 1966 Triumph TR6, the speedometer drive was moved from the layshaft in the gearbox to the rear wheel. The kickstart lever was made longer for easier starting. The final drive chain oiler at the rear of the primary case was eliminated. The adjusting screw on the clutch pressure plate was fattened to 3/8" starting with #DU31820.

FRAME & RUNNING GEAR CHANGES
The 1966 Triumph TR6 featured a change in steering head angle from 65-degrees to 62-degrees to quicken steering & a fairing lug was added to the neck. A new battery-mounting system used rubber bushings running on pegs, instead of rigid mounts. The swingarm was widened by 1/4" on the right side. A new fork stem & bottom lug tightened the turning radius. The rear sprocket went back to 46 teeth. A new, wider front brake drum increased brake swept area by 40%.

BODY WORK
A new petrol (fuel) tank was slimmer & available in 3- or 4-gallon capacities. A new tank badge came with it, perhaps the most popular ever, the now-famous "eyebrow badge", so-named for its large chromed 'eyebrow' above the "Triumph" logo (see photos). With the elimination of the rear chain oiler from the primary case, the oil tank was modified to accommodate, with an adjustable metering screw in the filler cap neck that controlled the amount of oil that was allowed to run down to the chain. Along with these mods, the top end oil line was now being fed off the top of the return pipe, rather than below the tank, as before. This led to weak & often erratic top end oiling which in turn caused premature rocker arm wear. A service kit was soon issued to reverse this.

NEW 12-VOLT ELECTRICS
Every 1966 Triumph TR6 (except the TR6C) got a 12-volt Zener Diode mounted to the battery box, as the whole system switched to 12 volts. Triumph Motorcycles opted for two Lucan SKZ9E 6-volt batteries hooked up in series to produce 12 volts. However, by #DU32985 they switched to a single Lucas PUZ5A 12-volt battery, with modified carrier to match. The 7-inch chromed headlight contained the ignition warning & high beam indicator lights (after #DU29247). The 12-volt Lucas MA12 coils were still located as before, although some US models got the smaller Siba 3200/1 coils. A Lucas 88SA light switch remained on the left-side cover as did a new ignition switch. The location of the Zener Diode had to be changed slightly due to overheating problems, starting with #DU40436.

1966 Triumph TR6 SPECIFICATIONS


Model Designations:

TR6S/S

TR6C

TR6SC

TR6R

TR6SR

Engine Type

Displacement

Bore & Stroke

Compression

Carburetor

Ignition

Engine output

Primary drive

Primary sprockets

Clutch

Gearbox

Ratios, overall:

1st, bottom

2nd

3rd

4th, top

Final drive

Final sprockets

Frame type

Suspension, front

Suspension, rear

Brake, front

Brake, rear

Tire, front

Tire, rear

Fuel Capacity

Wheelbase

Seat height

Ground clearance

Dry Weight


Street scrambler

Off-road/street (dual purpose/enduro)

Off-road, competition

Roadster

High-performance roadster

Air-cooled OHV vertical twin

649cc / 40.0 ci

71mm X 82mm / 2.79" X 3.23"

8.5:1

1- Amal Monobloc, 1-1/8"

Battery & coil, Lucas

42 bhp @ 6500 rpm

3/8" triplex chain X 84 links

Engine 29T X Clutch 58T

Multi-plate, wet

4-speed constant-mesh, right-foot shift


11.8:1

8.17:1

6.76:1

5.84:1

5/8" X .400" X 3/8" chain X 106 links

Gearbox 19T X Rear 47T

Brazed lug, full-cradle, single downtube

Telescopic fork, hydraulic damping

Swing arm, 2 Girling dampers

8" SLS drum, full-width

7" SLS drum, one-side

3.25" X 19" Dunlop

4.00" X 18" Dunlop

2.5 Imp gal (US)/4 Imp gal (UK & export)

54.5" / 140.3 cm

32.5" / 77.5 cm

5.0" / 12.7 cm

363 lbs / 165 kg

MORE TRIUMPH TR6 PAGES:
Triumph TR6
Triumph TR6, Pre-Unit (1956-1962)
.....1956
.....1957
.....1958
.....1959
.....1960
.....1961
.....1962
Triumph TR6, Unit-Construction (1963-1970)
.....1963
.....1964
.....1965
.....1966
.....1967
.....1968
.....1969
.....1970
Triumph TR6, Oil-in-Frame (1971-1972)
.....1971
.....1972
Triumph TR7
.....1973
.....1976

OTHER TRIUMPHS:
Triumph Bonneville
Triumph Trophy
Triumph Tiger
Triumph Thunderbird
Triumph Trident
Triumph X-75 Hurricane


Check out these TRIUMPH BOOKS


TALES OF TRIUMPH MOTORCYCLES & THE MERIDEN FACTORY


COMPLETE BOOK OF CLASSIC & MODERN TRIUMPHS


TRIUMPH BONNEVILLE & TR6


TRIUMPH MOTORCYCLES, THEIR RENAISSANCE & THE HINKLEY FACTORY


TRIUMPH SPEED TWIN & THUNDERBIRD BIBLE


HINKLEY TRIUMPH TRIPLES & FOURS ESSENTIAL BUYERS GUIDE


TRIUMPH PRODUCTION TESTERS’ TALES FROM THE MERIDEN FACTORY


TURNER’S TRIUMPHS: EDWARD TURNER & HIS TRIUMPH MOTORCYCLES


TRIUMPH TROPHY BIBLE


HINKLEY TRIUMPHS, THE FIRST GENERATION


BONNIE: THE DEVELOPMENT OF THE TRIUMPH BONNEVILLE


TRIUMPH: A CENTURY OF PASSION & POWER


TRIUMPH TWIN RESTORATION


CONENTRY’S BICYCLE HERITAGE


HOW TO RESTORE YOUR BSA ROCKET III/TRIUMPH TRIDENT


TRIUMPH & BSA TRIPLES: THE COMPLETE STORY OF THE TRIDENT & ROCKET 3


TIGER CUB BIBLE


TRIUMPH SINGLES: EARLY DAYS TO 1974 BY ROY BACON


BRITISH MOTORCYCLES: TRIUMPH


TRIUMPH MOTORCYCLE RESTORATION, PRE-UNIT


TRIUMPH PRE-UNIT TR5, 5T, 6T, T100 & T110 FACTORY SHOP MANUAL


TRIUMPH MOTORCYCLE RESTORATION


ILLUSTRATED TRIUMPH MOTORCYCLE BUYER’S GUIDE BY ROY BACON


FACTORY ORIGINAL TRIUMPH TWINS 1938-1962


TRIUMPH BONNEVILLE: PORTRAIT OF A LEGEND


TRIUMPH 650 & 750 TWIN REPAIR MANUAL 1963-1983, BY HAYNES


TRIUMPH MOTORCYCLES IN AMERICA


TRIUMPH BONNEVILLE 2001-2012 REPAIR MANUAL BY HAYNES


TRIUMPH BONNEVILLE: THE ESSENTIAL BUYERS GUIDE


TRIUMPH MOTORCYCLES TWINS & TRIPLES


TRUIMPH MOTORCYCLES: FROM SPEED TWIN TO BONNEVILLE


BOOK OF TRIUMPH TWINS BY CLYMER


TRIUMPH BONNEVILLE BIBLE, ALL MODELS 1959-1983


TRIUMPH TIGER CUB & TERRIER 1952-1968 REPAIR MANUAL BY HAYNES


TRIUMPH RACING MOTORCYCLES IN AMERICA


TRIUMPH MOTORCYCLES ILLUSTRATED WORKSHOP MANUAL 1945-1955 BY CLYMER


TRIUMPH 675 DAYTONA & STREET TRIPLE REPAIR MANUAL, 2006-2010


TRIUMPH TRIPLES & FOURS 1991-2004, HAYNES REPAIR MANAUL


TRIUMPH 350 & 500 UNIT TWINS ESSENTIAL BUYERS GUIDE


TRIUMPH TWIN RESTORATION BY ROY BACON


TRIUMPH BONNEVILLE & TR6 MOTORCYCLE RESTORATION GUIDE


TRIUMPH: RETURN OF THE LEGEND


BSA & TRIUMPH TRIPLES: GOLD PORTFOLIO


TRIUMPH MOTORCYCLE RESTORATION GUIDE: BONNEVILLE & TR6


TRIUMPH THUNDERBIRD 6T ROAD TEST 1966


TRIUMPH 500-750 TWINS 1963-1979, SERVICE, REPAIR & PERFORMANCE MANUAL


TRIUMPH TRIPLES


HOW TO RESTORE TRIUMPH TR5/250 & TR6


HOW TO RESTORE TRIUMPH TRIDENT T150/T160


TRIUMPH THRUXTON BONNEVILLE 1959-1969


TRIUMPH TIGER 800 SERVICE MANUAL 2010-2014, HAYNES


TRIUMPH TT600 MOTORCYCLE SERVICE MANUAL


TRIUMPH MOTORCYCLES


ORIGINAL TRIUMPH BONNEVILLE


TRIUMPH, BY ROY BACON


TRIUMPH ILLUSTRATED WORKSHOP MANUAL 1937-1951 BY ROY BACON


TRIUMPH 500 UNIT TWINS 1958-1973 REPAIR MANUAL, BY HAYNES


TRIUMPH T110R DAYTONA 1966-1969


TRIUMPH OWNERS MANUAL: UNIT CONSTRUCTION 350 & 500 TWINS

TRIUMPH INSTRUCTION MANUAL: TRW 499cc SV TWIN


TRIUMPH SPEED TWIN INSTRUCTION BOOK FOR 1939


TRIUMPH BONNEVILLE YEAR-BY-YEAR


CHILTON’S TRIUMPH MOTORCYCLE REPAIR & TUN-UP GUIDE


2010-14 TRIUMPH TIGER 800 HAYNES SERVICE MANUAL


TRIUMPH 650 & 750 TWINS: BONNEVILLE, TIGER, TROPHY & THUNDERBIRD


TRIUMPH MOTORCYCLE RESTORATION: PRE-UNIT, BY TIM REMUS


TRIUMPH MOTORCYCLE RESTORATION, BY TIM REMUS


TRIUMPH BONNEVILLE ROAD TEST PORTFOLIO, 2001-2008


TRIUMPH TRIDENT & BSA ROCKET 3 OWNERS WORKSHOP MANUAL, BY HAYNES


HINKLEY TRIUMPHS: THE FIRST GENERATION


TRIUMPH FUEL INJECTED TRIPLES 1997-2000


TRIUMPH SINGLES: EARLY DAYS TO 1974, BY ROY BACON


TRIUMPH PRE-UNIT TWINS WORKSHOP MANUAL, BY HAYNES


TRIUMPH DAYTONA, SPEED TRIPLE, SPRINT & TIGER 1995-2005 HAYNES SHOP MANUAL


TRIUMPH TIGER 100 & DAYTONA


McQUEEN’S MACHINES: THE CARS & BIKES OF A HOLLYWOOD ICON


TRIUMPH TWENTY-ONE TO DAYTONA: THE C-CLASS 350 & 500 TWINS


TRIUMPH 750/900 TRIPLES & 1200 FOUR 1991-1999 HAYNES REPAIR MANUAL


TRIUMPH, THE LEGENDS SERIES


TRIUMPH MOTORCYCLES & CUSTOM BIKES


TRIUMPH MOTORCYCLES TWINS & TRIPLES, BY REMUS


TRIUMPH MOTORCYCLES: THEIR RENAISSANCE & THE HINKLEY FACTORY


TRIUMPH MOTORCYCLES FROM 1950-1988


TRIUMPH MOTORCYCLES: THE GOLDEN YEARS


THE SCRAPBOOK SERIES I - TRIUMPH


TRIUMPH DAYTONA 1991-2006 ROAD TEST PORTFOLIO


CYCLE WORLD ON TRIUMPH 1967-1972


TRIUMPH SPEED TWIN & THUNDERBIRD BIBLE


TRIUMPH BONNEVILLE: T120/T140, BY HAYNES


SAVE THE BONNEVILLE: THE INSIDE STORY OF THE MERIDEN CO-OP


TRIUMPH: THE RACING STORY


TRIUMPH PRE-UNIT TWINS


LITTLE BOOK OF BRITISH MOTORCYCLES: TRIUMPH


CHILTON’S NEW REPAIR & TUNE-UP GUIDE FOR TRIUMPH MOTORCYCLES


THE TRIUMPH STORY: RACING & PRODUCTION MODELS 1902 TO PRESENT


TRIUMPH 1050 SPRINT, SPEED TRIPLE & TIGER, HAYNES REPAIR MANUAL


ILLUSTRATED TRIUMPH MOTORCYCLE BUYERS GUIDE POST-1945, ROY BACON


COMPLETE BOOK OF CLASSIC & MODERN TRIUMPHS


TRIUMPH BONNEVILLE


TIGER 100/DAYTONA: DEVEOPMENT HISTORY OF THE 500 TWIN


TOURING TRIUMPH TWINS, 3T, 5T, 6T, 3TA & 5TA, 1938-1966 BY ROY BACON


FACTORY TRIUMPH MOTORCYCLE SERVICE MANUAL


TRIUMPH CYCLES PATENT COLLECTION


TRIUMPH MOTORCYCLE OWNERS HANDBOOK, ALL MODELS 1937-1951


TRIUMPH MOTORCYCLES: A PRACTICAL GUIDE TO ALL MODELS FROM 1937




CHILTON’S REPAIR & TUNE-UP GUIDE, TRIUMPH THROUGH 1972


OVERHAUL MANUAL FOR TRIUMPH 3-CYLINDER ENGINE


TRIUMPH BONNEVILLE T120, 1959-1974, BY ROY BACON


TRIUMPH TIGER T100 & T110, 1939-1961, BY ROY BACON


TRIUMPH T90 & T100 UNIT TWINS, 1960-1974, BY ROY BACON


TRIUMPH REPLACEMENT PARTS CATALOGUE, 1972 TRIDENT T150


TRIUMPH TRIDENT SUPER PROFILE


TRIUMPH BONNEVILLE GOLD PORTFOLIO, 1959-1983


1969 TRIUMPH TROPHY 250 REPLACEMENT PARTS CATALOGUE


TRIUMPH 650 & 750 TWIN OWNERS WORKSHOP MANUAL


TRIUMPH: RED HOT BIKES


1966 TRIUMPH REPLACEMENT PARTS CATALOG #6: 3TA, 5TA, T90 & T100S/S


1961 TRIUMPH REPLACEMENT PARTS CATALOG: TWNETY-ONE, SPEED TWIN, TIGER 100


BONNEVILLE: THE WORLD’S FASTEST MOTORCYCLES


TRIUMPH WORKSHOP MANUAL FOR 750 BONNEVILLE & TIGER


TRIUMPH BONNEVILLE & TR6 BY TIM REMUS


TRIUMPH 650 & 750 UNIT TWINS 1963-1983, HAYNES REPAIR MANUAL


TRIUMPH OWNERS HANDBOOK FOR 1973 BONNEVILLE & TIGER


TRIUMPH PRE-UNIT TWINS WORKSHOP MANUAL


TRIUMPH 350/500 TWINS WORKSHOP MANUAL






Please visit our
MOTORCYCLE BOOK STORE


Take a tour of our site...

HOME PAGE
Triumph Motorcycles
.....Bonneville
.....Tiger
.....Trophy
.....TR6
.....TR7
.....Trident
.....X-75 Hurricane
.....6T Thunderbird
.....5T Speed Twin
BSA Motorcycles
.....A65
.....A10
.....A7
.....Gold Star
.....Bantam
.....Rocket 3
Norton Motorcycles
.....Commando
.....Atlas
.....Dominator
.....Manx
Matchless-AJS Motorcycles
.....G3
.....G9
.....G12
.....G80
AMC-Associated Motor Cycles
Royal Enfield Motorcycles
.....Interceptor
.....Bullet
Ariel Motorcycles
.....Square Four
.....Red Hunter
Vincent Motorcycles
.....Black Shadow
.....Comet
Velocette Motorcycles
.....KSS
.....LE
.....MAC
.....Thruxton
Rickman Motorcycles
Japanese Motorcycles
.....Honda
.....Kawasaki
.....Suzuki
.....Yamaha
Cafe Racers
....Triumph Cafe Racers
.....Norton Cafe Racers
.....Other Cafe Racers
Choppers & Bobbers
.....Choppers
.....Triumph Choppers
.....BSA Choppers
.....Rat Bikes
Classic Racing Motorcycles

Classic Motorcycle Events
.....Auctions
.....Shows
.....Rides
Classic Motorcycle Restoration
Classic Motorcycle Shops
Classic Motorcycle Clubs
Classic Motorcycle Photo Gallery
Send us Pictures of YOUR BIKE
YOUR BIKE Pictures

HOME PAGE
.....About Us
.....Site Map
.....CONTACT US
.....Please visit our BLOG
.....Subscribe to our FREE e-zine BRIT IRON
.....BRIT IRON E-zine Back Issues

Visit our STORE
.....Motorcycle Books
.....Motorcycle Magazines
.....Motorcycle Calendars
.....Motorcycle Helmets
.....GoPro Cameras

Crazy about cars, too? Check out our sister site:
www.American-Muscle-Cars.net

Back to top - 1966 Triumph TR6
1/26/16

Learn how to BUILD YOUR OWN WEBSITE, like I did.

2016 CALENDARS


Please visit our
MOTORCYCLE BOOK STORE


Subscribe to your favorite
MOTORCYCLE MAGAZINES





Classic Brit Bike
2016 Calendar


Check out all our
MOTORCYCLE CALENDARS


We now sell
GoPro CAMERAS




BIKES FOR SALE!
Check out our
FREE
Classifed Ads


Get your next
MOTORCYCLE HELMET
here


NEW PAGES
added this month:

Ariel Red Hunter
1939 Red Hunter
1947 Red Hunter
1948 Red Hunter
1949 Red Hunter
1954 Red Hunter
1957 Red Hunter
Velocette Thruxton
1966 Thruxton
1969 Thruxton
1954 Triumph Speed Twin
Clubmans Show 2016
2016 Hanford Motorcycle Show
2016 Norton Rally
2016 Pacific Coast Dream Machines Show
1934 BSA Blue Star
Triumph T140W TSS
Enjoy. More coming soon...