Data as of: DVSA MOT results to 2025
Yamaha XF 50 Giggle vs Piaggio NRG
The Yamaha XF 50 Giggle passes its MOT first time more often than the Piaggio NRG: 86.2% vs 65.5%, a 20.7-point lead.
MOT reliability, side by side
| Metric | Yamaha XF 50 Giggle | Piaggio NRG |
|---|---|---|
| First-time pass rate | 86.2% | 65.5% |
| Outright fail rate | 8.1% | 27.4% |
| Vs comparable bikes (age & mileage adjusted) | +12.0 pts | -6.0 pts |
| Engine size | 49cc | 49cc |
| Rank among all models | #2148 of 5428 | #4992 of 5428 |
| Median miles at test | 6,583 | 9,874 |
| MOT tests analysed | 1,129 | 40,458 |
| Most common failure | tyres and wheels | 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 | Yamaha XF 50 Giggle | Piaggio NRG |
|---|---|---|
| Lights & signalling | 3.3% | 15.0% |
| Steering & suspension | 2.4% | 15.5% |
| Brakes | 1.4% | 10.2% |
| Tyres & wheels | 3.3% | 4.7% |
| Fuel & exhaust | 0.6% | 3.8% |
| Structure & body | 0.5% | 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 | Yamaha XF 50 Giggle | Piaggio NRG |
|---|---|---|
| 2018 | 96.5% | 69.2% |
| 2019 | 90.3% | 68.0% |
| 2020 | 82.1% | 71.8% |
| 2021 | 89.4% | 72.9% |
| 2022 | 79.7% | 74.8% |
| 2023 | 84.3% | 77.5% |
| 2024 | 82.9% | 81.9% |
| 2025 | 77.5% | 77.1% |
Each year mixes bikes of different ages, so a fleet that is getting older tends to slip.
Pass rate by mileage
| Mileage | Yamaha XF 50 Giggle | Piaggio NRG |
|---|---|---|
| 0k-10k miles | 88.3% | 71.3% |
| 10k-20k miles | 81.3% | 60.6% |
| 20k-30k miles | 86.7% | 55.7% |
Bands with fewer than 30 tests for either bike are left out.
Yamaha XF 50 Giggle vs Piaggio NRG FAQ
Which is more reliable, the Yamaha XF 50 Giggle or the Piaggio NRG?
The Yamaha XF 50 Giggle passes its MOT first time more often than the Piaggio NRG: 86.2% vs 65.5%, a 20.7-point lead. Adjusted for age, mileage and test class, the Yamaha XF 50 Giggle still comes out ahead: +12.0 points vs comparable bikes for the Yamaha XF 50 Giggle, -6.0 for the Piaggio NRG. An MOT checks roadworthiness items, not engine or gearbox internals.
What does the Yamaha XF 50 Giggle fail its MOT on most?
Lights & signalling: 3.3% of Yamaha XF 50 Giggle MOT tests failed on it, then tyres & wheels (3.3%).
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 Yamaha XF 50 Giggle or the Piaggio NRG?
At 20k-30k miles the Yamaha XF 50 Giggle passes first time more often: 86.7% for the Yamaha XF 50 Giggle vs 55.7% for the Piaggio NRG.
See each bike's full report (trend, mileage curve, failure breakdown and rivals) on its own page.