Data as of: DVSA MOT results to 2025
Ariel Leader vs Piaggio X9
The Ariel Leader passes its MOT first time more often than the Piaggio X9: 92.7% vs 77.0%, a 15.7-point lead.
MOT reliability, side by side
| Metric | Ariel Leader | Piaggio X9 |
|---|---|---|
| First-time pass rate | 92.7% | 77.0% |
| Outright fail rate | 3.0% | 17.5% |
| Engine size | 250cc | 244cc |
| Rank among all models | #344 of 5428 | #4065 of 5428 |
| Median miles at test | 15,045 | 12,186 |
| MOT tests analysed | 1,135 | 21,703 |
| Most common failure | lighting and signalling | steering and suspension |
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.
What fails, side by side
| Component | Ariel Leader | Piaggio X9 |
|---|---|---|
| Steering & suspension | 1.1% | 7.5% |
| Lights & signalling | 0.9% | 7.3% |
| Brakes | 1.4% | 6.5% |
| Tyres & wheels | 0.5% | 4.2% |
| Fuel & exhaust | 0.3% | 1.8% |
| Structure & body | 0.1% | 0.8% |
| Drive system | 0.2% | 0.0% |
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 | Ariel Leader | Piaggio X9 |
|---|---|---|
| 2010 | 94.4% | 75.1% |
| 2011 | 92.4% | 75.7% |
| 2012 | 94.6% | 74.8% |
| 2013 | 92.9% | 74.1% |
| 2014 | 91.3% | 75.5% |
| 2015 | 94.0% | 76.1% |
| 2016 | 97.1% | 76.3% |
| 2017 | 93.7% | 76.3% |
Each year mixes bikes of different ages, so a fleet that is getting older tends to slip.
Pass rate by mileage
| Mileage | Ariel Leader | Piaggio X9 |
|---|---|---|
| 0k-10k miles | 93.3% | 81.4% |
| 10k-20k miles | 91.7% | 75.8% |
| 20k-30k miles | 92.1% | 72.4% |
| 30k-40k miles | 88.3% | 70.1% |
| 40k-50k miles | 95.5% | 71.1% |
| 50k-60k miles | 92.7% | 72.1% |
Bands with fewer than 30 tests for either bike are left out.
Ariel Leader vs Piaggio X9 FAQ
Which is more reliable, the Ariel Leader or the Piaggio X9?
The Ariel Leader passes its MOT first time more often than the Piaggio X9: 92.7% vs 77.0%, a 15.7-point lead. An MOT checks roadworthiness items, not engine or gearbox internals.
What does the Ariel Leader fail its MOT on most?
Brakes: 1.4% of Ariel Leader MOT tests failed on it, then steering & suspension (1.1%).
What does the Piaggio X9 fail its MOT on most?
Steering & suspension: 7.5% of Piaggio X9 MOT tests failed on it, then lights & signalling (7.3%).
Which holds up better at high mileage, the Ariel Leader or the Piaggio X9?
At 50k-60k miles the Ariel Leader passes first time more often: 92.7% for the Ariel Leader vs 72.1% for the Piaggio X9.
See each bike's full report (trend, mileage curve, failure breakdown and rivals) on its own page.