Data as of: DVSA MOT results to 2025
Gilera Stalker vs Piaggio NRG
The Piaggio NRG passes its MOT first time more often than the Gilera Stalker: 65.5% vs 65.3%, a 0.2-point lead.
MOT reliability, side by side
| Metric | Gilera Stalker | Piaggio NRG |
|---|---|---|
| First-time pass rate | 65.3% | 65.5% |
| Outright fail rate | 25.9% | 27.4% |
| Vs comparable bikes (age & mileage adjusted) | -6.2 pts | -6.0 pts |
| Engine size | 49cc | 49cc |
| Rank among all models | #5002 of 5428 | #4992 of 5428 |
| Median miles at test | 10,853 | 9,874 |
| MOT tests analysed | 5,858 | 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 | Gilera Stalker | Piaggio NRG |
|---|---|---|
| Lights & signalling | 17.5% | 15.0% |
| Steering & suspension | 11.3% | 15.5% |
| Brakes | 9.0% | 10.2% |
| Tyres & wheels | 4.2% | 4.7% |
| Fuel & exhaust | 4.2% | 3.8% |
| Structure & body | 2.9% | 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 | Gilera Stalker | Piaggio NRG |
|---|---|---|
| 2017 | 69.7% | 72.0% |
| 2018 | 70.5% | 69.2% |
| 2019 | 52.9% | 68.0% |
| 2020 | 67.4% | 71.8% |
| 2021 | 75.0% | 72.9% |
| 2022 | 72.2% | 74.8% |
| 2023 | 65.9% | 77.5% |
| 2024 | 60.6% | 81.9% |
Each year mixes bikes of different ages, so a fleet that is getting older tends to slip.
Pass rate by mileage
| Mileage | Gilera Stalker | Piaggio NRG |
|---|---|---|
| 0k-10k miles | 72.5% | 71.3% |
| 10k-20k miles | 60.4% | 60.6% |
| 20k-30k miles | 56.4% | 55.7% |
| 30k-40k miles | 51.9% | 57.0% |
Bands with fewer than 30 tests for either bike are left out.
Gilera Stalker vs Piaggio NRG FAQ
Which is more reliable, the Gilera Stalker or the Piaggio NRG?
The Piaggio NRG passes its MOT first time more often than the Gilera Stalker: 65.5% vs 65.3%, a 0.2-point lead. Adjusted for age, mileage and test class the two are level (-6.2 vs -6.0 points against comparable bikes), so the raw gap is mostly down to how old and how used each fleet is. An MOT checks roadworthiness items, not engine or gearbox internals.
What does the Gilera Stalker fail its MOT on most?
Lights & signalling: 17.5% of Gilera Stalker MOT tests failed on it, then steering & suspension (11.3%).
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%).
Which holds up better at high mileage, the Gilera Stalker or the Piaggio NRG?
At 30k-40k miles the Piaggio NRG passes first time more often: 51.9% for the Gilera Stalker vs 57.0% for the Piaggio NRG.
See each bike's full report (trend, mileage curve, failure breakdown and rivals) on its own page.