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1979 Triumph T140E Bonneville
Traditional
2-cyl. 744cc/49hp
#1 Concours condition#1 Concours
#2 Excellent condition#2 Excellent
#3 Good condition#3 Good
$5,000*
-5.7%
#4 Fair condition#4 Fair
Jun 2024
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1973-1980 Triumph Bonneville T140 stats
Highest sale
$20,720
Lowest sale
$2,200
Most recent sale
$4,850
Sales
138
Past sales
$4,850
1973 Triumph T140V Bonneville Base
4400 M
North America
Feb 18, 2025Bring a Trailer
View details
$13,200
1977 Triumph T140J Bonneville Silver Jubilee
1145 M
Standard
North America
Feb 1, 2025Mecum Auctions
View details
$5,500
1979 Triumph T140D Bonneville Special
9630 M
Standard
North America
Jan 31, 2025Mecum Auctions
View details
$7,700
1977 Triumph T140J Bonneville Silver Jubilee
17003 M
North America
Jan 30, 2025Mecum Auctions
View details
$3,850
1973 Triumph T140V Bonneville Base
14279 M
Standard
North America
Jan 30, 2025Mecum Auctions
View details
$6,050
1979 Triumph T140D Bonneville Special
4064 M
Standard
North America
Jan 30, 2025Mecum Auctions
View details
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Model overview
Model description
The words “pedantic bureaucracy” came up in describing Triumph’s operations during the1970s, but the company still managed to field a desirable motorcycle in the 1979 T140E Bonneville. The past years’ insistence that Triumph was the marque for expert riders would be amplified by new advertising to come, which asserted the Bonneville was “a motorcycle for men.” The copy said “every detail [was] carefully planned by men who ride—and ride hard.” This appeal always worked. The T140E Bonneville had been introduced in ’78 with modifications that met new standards set by the United States Environmental Protection Agency, who decreed against escaping fuel and oil vapors.
The familiar air-cooled, overhead-valve 744cc parallel twin got a makeover then, receiving a new cylinder head. With the compression ratio reduced to 7.9:1, output fell to 49 horsepower at 6,200 rpm. For 1979, the engine adopted Lucas Rita electronic ignition, one of the biggest steps forward for the Bonneville before electric start was added. New Veglia instruments were added, along with Lucas switches and a lockable seat with a rear rack. There were few other changes. Three color combinations on the teardrop tank tantalized buyers: red with black flashes, black and silver, and a quite striking scheme using dark blue with silver flashes. This was an aging motorcycle, but even with a bit of clutter—the left-foot shift lever sticking from the primary case cover, for example—the Bonneville still had hard-to-match heritage and character. It made a statement from 100 yards away.
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Common Questions
The value of a 1979 Triumph T140E Bonneville can vary greatly depending on its condition, mileage, options, and history. Typically, you can expect to pay around $5,000 for a 1979 Triumph T140E Bonneville in good condition with average spec.
The highest selling price of a 1979 Triumph T140E Bonneville at auction over the last three years was $10,450. The highest prices are usually reserved for rare or exceptionally well-maintained examples with desirable features or modifications and excellent history.
The lowest selling price of a 1979 Triumph T140E Bonneville at auction over the last three years was $3,350. The lowest prices are usually paid for examples that have extensive maintenance needs, differ greatly from their original configuration, or have accident histories or title problems.
In the last three years there have been 7 1979 Triumph T140E Bonnevilles sold at public auction.
The most recent auction sale of a 1979 Triumph T140E Bonneville was $4,191 on January 23, 2025 by Car and Classic.
Many factors can increase a car's value including excellent condition, exceptional originality, a recent restoration, low mileage, unique provenance, desirable options, popular or unique color choices, and excellent maintenance records. Upgrades and modifications that enhance performance or aesthetics can also add value.
Factors that can decrease a car's value include unusually high mileage, poor maintenance history, visible wear and tear, accidents or damage, title issues, and gaps in ownership history. Additionally, less popular color choices and extensive modifications that don't appeal to a broad audience can reduce value.
Mileage plays a significant role in a classic car’s value. Lower mileage usually increases value because it indicates a higher degree of originality, is rarer, and suggests less wear and tear. However, cars with exceptionally low mileage may also have maintenance needs due to lack of use. Whether someone should pay more for a vehicle with lower miles will depend on how they plan on using it, and the vehicle's specific condition.
The value of modified cars differs widely based on the type and quality of modifications. While some modifications can significantly increase value, especially performance enhancements and high-quality custom work, others may not add much or could even detract from the car’s value if they appeal to only a limited audience.