Pass rate over time
The JET 4 50's first-time pass rate has fallen 21.9 points since 2014, 76.9% to 55.0%.
Pass rate by mileage
A low-mileage JET 4 50 passes first time 79.3% of the time; by 20k that's 70.5%.
First-time pass rate by odometer reading at test, 10,000-mile bands for this model. Mileage is the strongest reliability signal. See the full curve.
What fails on a JET 4 50
| Component group | Share of defects | Defects | % of defects |
|---|---|---|---|
| brakes |
|
42 | 29 |
| steering and suspension |
|
22 | 15.2 |
| lighting and signalling |
|
19 | 13.1 |
| lamps and reflectors |
|
15 | 10.3 |
| fuel and exhaust |
|
12 | 8.3 |
| tyres and wheels |
|
9 | 6.2 |
| suspension |
|
8 | 5.5 |
| tyres |
|
7 | 4.8 |
| steering |
|
6 | 4.1 |
| structure and attachments |
|
5 | 3.4 |
Defects recorded against failed normal tests, 2005–2025, grouped by DVSA inspection section. One test can record multiple defects.
How rivals compare
On first-time pass rate the JET 4 50 beats 4 of its 4 closest rivals (PEUGEOT SPEEDFIGHT, PIAGGIO ZIP, PIAGGIO NRG).
Rivals share this bike's type and sit within ±30% of its engine capacity, ≥ 5,000 tests. Card colour = better/worse first-time pass rate than the JET 4 50.
Pass rate by registration year
Best year to buy used: 2010 (73.0% pass). Weakest: 2011 (71.5%).
First-time pass rate by the year each bike was first registered (cohorts with ≥ 50 tests). Older cohorts are survivors: the worst examples have already left the road, which tends to lift the earliest years.