The pass rate is the MOT first-time pass: a roadworthiness check of the items an MOT covers (brakes, lights, tyres, steering, structure, emissions), not a full mechanical inspection of engine or gearbox internals. It is a reliability signal, not a complete measure of mechanical reliability. What this measures.
“vs expected” adjusts for age, mileage and test class, so a cherished classic and a hard-used commuter are compared fairly. How this works.
Pass rate over time
The SX 50's first-time pass rate has fallen 5.1 points since 2013, 56.7% to 51.6%.
What fails on a SX 50
| Component group | Share of defects | Defects | % of defects |
|---|---|---|---|
| lighting and signalling |
|
152 | 36 |
| steering and suspension |
|
104 | 24.6 |
| brakes |
|
66 | 15.6 |
| drive system |
|
37 | 8.8 |
| body and structure |
|
16 | 3.8 |
| structure and attachments |
|
10 | 2.4 |
| reg plates and vin |
|
10 | 2.4 |
| tyres and wheels |
|
10 | 2.4 |
| lamps and reflectors |
|
10 | 2.4 |
| fuel and exhaust |
|
7 | 1.7 |
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 SX 50 beats 0 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 SX 50.
Compare with any bike
More CPI models
Pass rate by registration year
Best year to buy used: 2008 (47.0% pass). Weakest: 2007 (42.0%).
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.
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