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.
Pass rate over time
The 18's first-time pass rate has fallen 6.5 points since 2006, 100.0% to 93.5%.
Pass rate by mileage
A low-mileage 18 passes first time 92.7% of the time; by 50k that's 100.0%.
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 18
| Component group | Share of defects | Defects | % of defects |
|---|---|---|---|
| lighting and signalling |
|
3 | 30 |
| tyres and wheels |
|
3 | 30 |
| brakes |
|
2 | 20 |
| steering and suspension |
|
2 | 20 |
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 18 beats 4 of its 4 closest rivals (KAWASAKI ZX-6R, SUZUKI GSF600, YAMAHA FZS600).
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 18.
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