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 WM20's first-time pass rate has risen 6.1 points since 2009, 93.9% to 100.0%.
What fails on a WM20
| Component group | Share of defects | Defects | % of defects |
|---|---|---|---|
| tyres and wheels |
|
3 | 30 |
| steering and suspension |
|
2 | 20 |
| driving controls |
|
1 | 10 |
| brakes |
|
1 | 10 |
| reg plates and vin |
|
1 | 10 |
| lighting and signalling |
|
1 | 10 |
| drive system |
|
1 | 10 |
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 WM20 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 WM20.
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