1951 Triumph Thunderbird

The 1951 Triumph Thunderbird carried one model designation: "6T", and was known as the 6T Thunderbird, 6T or simply T-Bird. All 1951 Triumph Thunderbird 6T's were 650's & came equipped essentially the same, with the same rigid frame & sprung rear hub, and the same setup throughout. Unlike the later Triumph TR6 which came in a variety of flavors (ie: high pipes, low pipes, competition, etc.).

1951 TRIUMPH THUNDERBIRD - RIDING THE WAVE
The 1951 Triumph Thunderbird carried over largely unchanged from its 1950 model year introduction. There were the usual incremental improvements to engine & gearbox, mostly designed to improve reliability, ease vibration or simplify assembly. But Triumph Motorcycles & their ace designer Edward Turner, knew they had a hit on their hands & left things well enough alone with the 1951 Triumph Thunderbird. After all, don't fix it if it ain't broke.

1951 TRIUMPH THUNDERBIRD - OVERVIEW
On the 1951 Triumph Thunderbird, the Amal carburetor was increased in size from 1 inch to 1-1/16 inch. The 7-inch SLS front brake was also improved. The same brazed-lug rigid frame soldiered on with the notorious sprung rear hub trying to pass as rear suspension. It was an atrocious compromise implemented (indeed invented) by none other than Edward Turner himself as a way to delay the expensive retooling needed to adopt a more contemporary swing arm rear suspension. It was crude & ineffective. It didn't absorb bumps very well & looseness would develop in the hub leading to uncontrolled wheel movements & erratic handling as the result.

1951 TRIUMPH THUNDERBIRD - COLOR SCHEMES
On a more positive note, the color scheme improved for the 1951 Triumph Thunderbird. Called Polychromatic Blue, it's a handsome metallic blue (pictured here). The Triumph T-Bird had its own logo, the so-called "Paper Dart" (unofficial nickname), pictured on the headlight nacelle above. This would later be cast into the primary cover.
The 1951 Triumph Thunderbird was a handsome machine in its day. The headlight nacelle of the 1951 Triumph Thunderbird incorporated the headlight, gauges (clocks), and handlebar mounts all in one neat package. This was a British innovation, intended to help keep the bikes clean in typically inclement British weather & also make them easy to clean, once ridden. The full fenders on this 1951 Triumph Thunderbird are also in keeping with that school of thought. It wasn't until the American Triumph dealers made a fuss that Triumph Motorcycles began to get lean & mean, starting with the 1956 Triumph TR6.


1951 Triumph 6T Thunderbird
SPECIFICATIONS


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 drive sprockets

Frame Type

Suspension, front

Suspension, rear

Brake, front

Brake, rear

Tire, front

Tire, rear

Wheelbase

Seat Height

Ground Clearance

Fuel capacity

Dry weight

Air-cooled OHV vertical twin, non-unit

649cc / 40.0 ci

71mm X 82mm / 2.79" X 3.23"

8.5:1 (US & export); 7.0:1 (UK)

1- Amal Monobloc, 1-1/16"

Lucas magneto

34 bhp @ 6500 rpm

1/2" X .335" X 5/16" chain, 70 links

24T X 43T

Multi-plate, wet

4-speed constant mesh, right foot shift


11.9:1

8.25:1

5.81:1

4.88

5/8" X .400" X 3/8" chain, 101 links

18T X 46T

Brazed lug, rigid

Telescopic fork, hydraulic damping

Sprung rear hub, rigid frame

7" SLS drum

7" SLS drum

3.25" X 19"

3.50" X 19"

55.25" / 140.3 cm

31" / 77.5 cm

5" / 12.7 cm

3 Imp gal (US); 4 Imp gal (UK & export)

370 lbs / 168 kg


MORE THUNDERBIRD PAGES:
Triumph 6T Thunderbird
.....Pre-Unit Thunderbird
.....1950
.....1951
.....1952
.....1953
.....1954
.....1955
.....1956
.....1957
.....1958
.....1959
.....1960
.....Unit-Construction Triumph Thunderbird
.....1963
MORE TRIUMPHS:
Triumph T120 & T140 Bonneville
Triumph TR6
Triumph TR7
Triumph T110 & T110 Tiger
Triumph 6T Thunderbird
Triumph 5T Speed Twin
Triumph T150 & T160 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


BONNIE: THE DEVELOPMENT OF THE TRIUMPH BONNEVILLE


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
Ariel Motorcycles
.....Square Four
Vincent Motorcycles
.....Black Shadow
.....Comet
Velocette Motorcycles
.....KSS
.....LE
.....MAC
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
American Pickers TV show
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

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

Back to top - 1951 Triumph Thunderbird
1/26/16

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

Visit our
FACEBOOK PAGE
and "LIKE" us!





ULTIMATE MOTORCYCLES
2015 Wall Calendar


Check out all our
MOTORCYCLE CALENDARS


Visit our
FACEBOOK PAGE
and "LIKE" us!