Data as of: DVSA MOT results to 2025
Indian Motorcycle Scout vs Triumph Thunderbird
The Indian Motorcycle Scout passes its MOT first time more often than the Triumph Thunderbird: 92.2% vs 87.8%, a 4.4-point lead.
MOT reliability, side by side
| Metric | Indian Motorcycle Scout | Triumph Thunderbird |
|---|---|---|
| First-time pass rate | 92.2% | 87.8% |
| Outright fail rate | 3.8% | 6.2% |
| Vs comparable bikes (age & mileage adjusted) | +3.3 pts | +2.1 pts |
| Engine size | 1,133cc | 885cc |
| Rank among all models | #434 of 5428 | #1669 of 5428 |
| Median miles at test | 5,240 | 13,106 |
| MOT tests analysed | 3,775 | 56,312 |
| Most common failure | lamps and reflectors | brakes |
First-time outcomes on normal tests, 2005–2025. "Most common failure" is the component group with the most recorded defects on failed tests. Read pass rates against test counts: a smaller sample is noisier. Source: DVSA anonymised MOT results.
"Vs comparable bikes" is the first-time pass rate minus the rate expected for each bike's own mix of age, mileage and test class, in percentage points: positive means better than comparable bikes. How this works.
What fails, side by side
| Component | Indian Motorcycle Scout | Triumph Thunderbird |
|---|---|---|
| Lights & signalling | 1.6% | 2.2% |
| Brakes | 0.7% | 2.0% |
| Steering & suspension | 1.0% | 1.3% |
| Tyres & wheels | 0.5% | 1.6% |
| Structure & body | 0.7% | 0.3% |
| Fuel & exhaust | 0.0% | 0.4% |
| Drive system | 0% | 0.2% |
A test that fails on two components counts once in each. Component links go to the bikes most likely to fail on it.
Pass rate by test year
| Test year | Indian Motorcycle Scout | Triumph Thunderbird |
|---|---|---|
| 2018 | 91.6% | 87.8% |
| 2019 | 89.8% | 87.7% |
| 2020 | 96.2% | 88.8% |
| 2021 | 91.2% | 88.2% |
| 2022 | 90.4% | 88.9% |
| 2023 | 92.8% | 90.5% |
| 2024 | 92.5% | 88.2% |
| 2025 | 92.9% | 89.5% |
Each year mixes bikes of different ages, so a fleet that is getting older tends to slip.
Pass rate by mileage
| Mileage | Indian Motorcycle Scout | Triumph Thunderbird |
|---|---|---|
| 0k-10k miles | 93.2% | 90.5% |
| 10k-20k miles | 88.8% | 87.3% |
| 20k-30k miles | 84.9% | 85.4% |
Bands with fewer than 30 tests for either bike are left out.
Indian Motorcycle Scout vs Triumph Thunderbird FAQ
Which is more reliable, the Indian Motorcycle Scout or the Triumph Thunderbird?
The Indian Motorcycle Scout passes its MOT first time more often than the Triumph Thunderbird: 92.2% vs 87.8%, a 4.4-point lead. Adjusted for age, mileage and test class, the Indian Motorcycle Scout still comes out ahead: +3.3 points vs comparable bikes for the Indian Motorcycle Scout, +2.1 for the Triumph Thunderbird. An MOT checks roadworthiness items, not engine or gearbox internals.
What does the Indian Motorcycle Scout fail its MOT on most?
Lights & signalling: 1.6% of Indian Motorcycle Scout MOT tests failed on it, then steering & suspension (1.0%).
What does the Triumph Thunderbird fail its MOT on most?
Lights & signalling: 2.2% of Triumph Thunderbird MOT tests failed on it, then brakes (2.0%).
Which holds up better at high mileage, the Indian Motorcycle Scout or the Triumph Thunderbird?
They are level: at 20k-30k miles the Indian Motorcycle Scout passes 84.9% first time and the Triumph Thunderbird 85.4%.
See each bike's full report (trend, mileage curve, failure breakdown and rivals) on its own page.