Triumph Thunderbird MOT Pass Rate
Overall pass rate across all manufacture years, based on 45,238 real MOT test results. Failure rate: 12.2%.
Data from official DVSA MOT testing records
Triumph Thunderbird MOT Reliability Overview
The Triumph Thunderbird is a relatively common sight on UK roads, with 45,238 MOT test results recorded in our database spanning 32 manufacture years. It has an overall MOT pass rate of 87.8% and a failure rate of 12.2%, which is well above the UK average of approximately 37%.
Based on this data, the Triumph Thunderbird earns a "Excellent" reliability rating. The average Triumph Thunderbird presents for MOT with approximately 16,609 miles on the clock. Manufacture year matters: 1960 models achieve the highest pass rate at 96.0%, while 1995 models have the lowest at 84.2%. This 11.8 percentage point difference suggests notable variation in build quality or component durability across production years.
The most common MOT failure for the Triumph Thunderbird is Motorcycle brakes, affecting 5.1% of all tests. Brake-related failures include worn brake pads, corroded brake discs, leaking brake lines, and faulty brake servos. These are safety-critical components — any brake deficiency will result in an MOT fail. The second most common issue is Motorcycle lighting and signalling at 4.4%. Motorcycle lamps and reflectors rounds out the top three at 3.4%. Together, these top 3 failure categories account for a significant portion of all MOT failures for this model.
Top failures across all manufacture years combined. Individual year pages may show different top failures.
What Fails Most
Best Year to Buy
📈 How Each Vintage Ages
Tracking how each manufacture year's MOT pass rate changes as the car ages. Showing 16 vintages — click year chips to highlight.
Multi-line chart showing how different Triumph Thunderbird vintages degrade over time, from age 3 to 29 years.
Only vintages with 100+ tests in at least 3 different test years are shown. Fleet average is the UK-wide pass rate for all cars at each age.
📉 How Age Affects Reliability
MOT failure rate by vehicle age for the Triumph Thunderbird. The dashed red line marks when the manufacturer warranty typically expires (3 years).
Line chart showing MOT failure rate by vehicle age from 3 to 20 years, with warranty expiry marked at 3 years.
💡 What does the warranty cliff mean?
The Triumph Thunderbird actually sees a 4% decrease in failure rate after the warranty period. This is likely due to survivorship bias — unreliable cars are already off the road by this age. Peak failure occurs at age 14 (14.5% fail rate).
Note: pass rates may improve for very old vehicles due to survivorship bias — only well-maintained cars remain on the road.
Pass Rate by Manufacture Year
* High Fail Rate badge indicates an MOT pass rate below 65% (failure rate above 35%).
What Fails on This Car?
Click a category to see specific failure items.
View as table
| Rank | Failure Category | Rate (%) | Count |
|---|---|---|---|
| 1 | Motorcycle Brakes | 5.4% | 2,460 |
| 2 | Motorcycle Lighting And Signalling | 4.7% | 2,119 |
| 3 | Motorcycle Lamps And Reflectors | 3.4% | 1,520 |
| 4 | Motorcycle Tyres And Wheels | 2.2% | 1,005 |
| 5 | Motorcycle Steering And Suspension | 1.9% | 856 |
| 6 | Motorcycle Tyres | 1.4% | 612 |
| 7 | Motorcycle Structure And Attachments | 1.0% | 437 |
| 8 | Motorcycle Fuel And Exhaust | 0.9% | 423 |
| 9 | Motorcycle Drive System | 0.8% | 383 |
| 10 | Motorcycle Suspension | 0.7% | 296 |
| 11 | Motorcycle Reg Plates And Vin | 0.5% | 214 |
| 12 | Identification Of The Vehicle | 0.3% | 147 |
| 13 | Motorcycle Audible Warning (Horn) | 0.3% | 143 |
| 14 | Motorcycle Steering | 0.2% | 109 |
| 15 | Motorcycle Body And Structure | 0.2% | 76 |
Failures per 10,000 Miles
avg. 16,609 miFor every 10,000 miles driven, this shows what percentage of MOT tests fail for each category. This accounts for how far cars are actually driven, not just raw pass/fail counts.
View as table
| Category | Rate / 10K mi | Raw % | Count |
|---|---|---|---|
| Motorcycle brakes | 3.27 | 5.4% | 2,460 |
| Motorcycle lighting and signalling | 2.82 | 4.7% | 2,119 |
| Motorcycle lamps and reflectors | 2.02 | 3.4% | 1,520 |
| Motorcycle tyres and wheels | 1.34 | 2.2% | 1,005 |
| Motorcycle steering and suspension | 1.14 | 1.9% | 856 |
| Motorcycle tyres | 0.81 | 1.4% | 612 |
| Motorcycle structure and attachments | 0.58 | 1.0% | 437 |
| Motorcycle fuel and exhaust | 0.56 | 0.9% | 423 |
| Motorcycle drive system | 0.51 | 0.8% | 383 |
| Motorcycle suspension | 0.39 | 0.7% | 296 |
| Motorcycle reg plates and vin | 0.28 | 0.5% | 214 |
| Identification of the vehicle | 0.20 | 0.3% | 147 |
| Motorcycle audible warning (Horn) | 0.19 | 0.3% | 143 |
| Motorcycle steering | 0.15 | 0.2% | 109 |
| Motorcycle body and structure | 0.10 | 0.2% | 76 |
🚗 Similar Cars to Consider
Mileage at MOT
The average Triumph Thunderbird has 16,609 miles when tested for MOT.
📊 Mileage-Adjusted Failure Rate
How often this car fails MOT relative to how much it's driven — a fairer comparison than raw pass rate.
The Triumph Thunderbird has a mileage-adjusted failure rate of 7.35% per 10,000 miles driven. The average across all makes is 5.38%, so this model is worse than average.
About Triumph Thunderbird MOT Data
The Triumph Thunderbird is a relatively common sight on UK roads, with 45,238 MOT test results recorded in our database spanning 32 manufacture years. It has an overall MOT pass rate of 87.8% and a failure rate of 12.2%, which is well above the UK average of approximately 37%.
For Triumph Thunderbird owners, these results suggest a reliable vehicle that generally passes its MOT without major issues. Focus your pre-MOT checks on motorcycle brakes and motorcycle lighting and signalling for the best chance of a first-time pass. Use our detailed year-by-year breakdown and failure analysis below to understand how your specific Thunderbird is likely to perform.
Motorcycle brakes — 5.1% of failures
Motorcycle brakes issues account for 5.1% of MOT failures on the Triumph Thunderbird. Brake-related failures include worn brake pads, corroded brake discs, leaking brake lines, and faulty brake servos. These are safety-critical components — any brake deficiency will result in an MOT fail. Typical repair costs: £150–400. Pre-MOT check: Listen for squealing or grinding noises. Check brake pedal feel — if it feels spongy or goes to the floor, have the system inspected immediately. Look at brake pad thickness through the wheel spokes (minimum 3mm).
Motorcycle lighting and signalling — 4.4% of failures
Motorcycle lighting and signalling issues account for 4.4% of MOT failures on the Triumph Thunderbird. Motorcycle lighting and signalling issues are a common cause of MOT failure. Regular inspection and maintenance of these components helps ensure your vehicle passes its MOT. Typical repair costs: £100–400. Pre-MOT check: Have this system checked during regular servicing. Look for warning signs like unusual noises, vibrations, or dashboard warning lights.
Motorcycle lamps and reflectors — 3.4% of failures
Motorcycle lamps and reflectors issues account for 3.4% of MOT failures on the Triumph Thunderbird. Lighting failures cover all external lights: headlights, tail lights, brake lights, indicators, fog lights, and reflectors. A single blown bulb will cause an MOT fail. This is one of the most preventable failure categories. Typical repair costs: £5–50. Pre-MOT check: Walk around the car and check every light — headlights (dipped and main beam), side lights, tail lights, brake lights, indicators, hazard lights, reverse light, rear fog light, and number plate lights. Replace any blown bulbs before the test.
Frequently Asked Questions
What is the MOT pass rate for the Triumph Thunderbird?
Based on 45,238 MOT tests in our database, the Triumph Thunderbird has an overall pass rate of 87.8% (12.2% fail rate).
What are the most common MOT failures on a Triumph Thunderbird?
The top 3 reasons a Triumph Thunderbird fails its MOT are: 1. Motorcycle brakes (5.1%), 2. Motorcycle lighting and signalling (4.4%), 3. Motorcycle lamps and reflectors (3.4%). Check these areas before booking your MOT.
Is the Triumph Thunderbird reliable?
With a 12.2% MOT failure rate, the Thunderbird is more reliable than average compared to the UK average of ~40%.
What should I check before an MOT on my Triumph Thunderbird?
Based on failure data, focus on: Motorcycle brakes (5.1%); Motorcycle lighting and signalling (4.4%); Motorcycle lamps and reflectors (3.4%). These are the areas most likely to cause a fail. Also check all lights, tyres (minimum 1.6mm tread), and windscreen condition — these are quick wins that apply to all cars.
Based on DVSA anonymised MOT test data (2005–2024). Crown copyright, Open Government Licence v3.0.