Data as of: DVSA MOT results to 2025
Honda Z50J vs Piaggio NRG
The Honda Z50J passes its MOT first time more often than the Piaggio NRG: 91.7% vs 65.5%, a 26.2-point lead.
MOT reliability, side by side
| Metric | Honda Z50J | Piaggio NRG |
|---|---|---|
| First-time pass rate | 91.7% | 65.5% |
| Outright fail rate | 3.9% | 27.4% |
| Vs comparable bikes (age & mileage adjusted) | +11.1 pts | -6.0 pts |
| Engine size | 49cc | 49cc |
| Rank among all models | #524 of 5428 | #4992 of 5428 |
| Median miles at test | 1,677 | 9,874 |
| MOT tests analysed | 516 | 40,458 |
| Most common failure | lighting and signalling | lighting and signalling |
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 | Honda Z50J | Piaggio NRG |
|---|---|---|
| Lights & signalling | 2.5% | 15.0% |
| Steering & suspension | 1.6% | 15.5% |
| Brakes | 0% | 10.2% |
| Tyres & wheels | 0.2% | 4.7% |
| Fuel & exhaust | 0% | 3.8% |
| Structure & body | 0.2% | 2.5% |
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 | Honda Z50J | Piaggio NRG |
|---|---|---|
| 2006 | 85.0% | 64.7% |
| 2008 | 93.3% | 65.2% |
| 2009 | 91.2% | 62.2% |
| 2011 | 91.2% | 63.9% |
| 2012 | 90.0% | 63.4% |
| 2016 | 90.0% | 68.0% |
| 2017 | 100.0% | 72.0% |
Each year mixes bikes of different ages, so a fleet that is getting older tends to slip.
Honda Z50J vs Piaggio NRG FAQ
Which is more reliable, the Honda Z50J or the Piaggio NRG?
The Honda Z50J passes its MOT first time more often than the Piaggio NRG: 91.7% vs 65.5%, a 26.2-point lead. Adjusted for age, mileage and test class, the Honda Z50J still comes out ahead: +11.1 points vs comparable bikes for the Honda Z50J, -6.0 for the Piaggio NRG. An MOT checks roadworthiness items, not engine or gearbox internals.
What does the Honda Z50J fail its MOT on most?
Lights & signalling: 2.5% of Honda Z50J MOT tests failed on it, then steering & suspension (1.6%).
What does the Piaggio NRG fail its MOT on most?
Steering & suspension: 15.5% of Piaggio NRG MOT tests failed on it, then lights & signalling (15.0%).
See each bike's full report (trend, mileage curve, failure breakdown and rivals) on its own page.