Data as of: DVSA MOT results to 2025
KTM 640 Duke Ii vs Triumph Street Triple R
The Triumph Street Triple R passes its MOT first time more often than the KTM 640 Duke Ii: 87.7% vs 80.6%, a 7.1-point lead.
MOT reliability, side by side
| Metric | KTM 640 Duke Ii | Triumph Street Triple R |
|---|---|---|
| First-time pass rate | 80.6% | 87.7% |
| Outright fail rate | 9.9% | 6.0% |
| Vs comparable bikes (age & mileage adjusted) | -6.5 pts | +1.1 pts |
| Engine size | 625cc | 675cc |
| Rank among all models | #3459 of 5428 | #1695 of 5428 |
| Median miles at test | 8,889 | 10,588 |
| MOT tests analysed | 4,182 | 20,614 |
| Most common failure | lighting and signalling | lamps and reflectors |
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 | KTM 640 Duke Ii | Triumph Street Triple R |
|---|---|---|
| Lights & signalling | 6.0% | 2.7% |
| Tyres & wheels | 2.2% | 1.2% |
| Steering & suspension | 2.2% | 1.0% |
| Brakes | 1.5% | 1.6% |
| Structure & body | 0.5% | 0.8% |
| Drive system | 1.1% | 0.1% |
| Fuel & exhaust | 0.7% | 0.1% |
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 | KTM 640 Duke Ii | Triumph Street Triple R |
|---|---|---|
| 2018 | 82.3% | 87.9% |
| 2019 | 80.6% | 87.9% |
| 2020 | 81.2% | 87.5% |
| 2021 | 72.5% | 87.8% |
| 2022 | 83.2% | 85.9% |
| 2023 | 87.8% | 87.0% |
| 2024 | 84.1% | 88.0% |
| 2025 | 84.0% | 89.8% |
Each year mixes bikes of different ages, so a fleet that is getting older tends to slip.
Pass rate by mileage
| Mileage | KTM 640 Duke Ii | Triumph Street Triple R |
|---|---|---|
| 0k-10k miles | 83.3% | 91.0% |
| 10k-20k miles | 78.0% | 86.5% |
| 20k-30k miles | 74.8% | 82.0% |
| 30k-40k miles | 65.1% | 78.2% |
Bands with fewer than 30 tests for either bike are left out.
KTM 640 Duke Ii vs Triumph Street Triple R FAQ
Which is more reliable, the KTM 640 Duke Ii or the Triumph Street Triple R?
The Triumph Street Triple R passes its MOT first time more often than the KTM 640 Duke Ii: 87.7% vs 80.6%, a 7.1-point lead. Adjusted for age, mileage and test class, the Triumph Street Triple R still comes out ahead: -6.5 points vs comparable bikes for the KTM 640 Duke Ii, +1.1 for the Triumph Street Triple R. An MOT checks roadworthiness items, not engine or gearbox internals.
What does the KTM 640 Duke Ii fail its MOT on most?
Lights & signalling: 6.0% of KTM 640 Duke Ii MOT tests failed on it, then tyres & wheels (2.2%).
What does the Triumph Street Triple R fail its MOT on most?
Lights & signalling: 2.7% of Triumph Street Triple R MOT tests failed on it, then brakes (1.6%).
Which holds up better at high mileage, the KTM 640 Duke Ii or the Triumph Street Triple R?
At 30k-40k miles the Triumph Street Triple R passes first time more often: 65.1% for the KTM 640 Duke Ii vs 78.2% for the Triumph Street Triple R.
See each bike's full report (trend, mileage curve, failure breakdown and rivals) on its own page.