Frequently asked questions
What the MOT data can tell you about a bike, what it can't, and how to read every number on this site. Definitions live in the glossary; the full small print is in the methodology.
What is a first-time MOT pass rate?
The share of normal MOT tests a bike passes at the first attempt, with no defects that require fixing. Retests and abandoned tests are excluded. Across all motorcycles it is 82.0% for 2005–2025.
What does “pass after rectification” (PRS) mean?
The tester found a defect but it was fixed there and then, and the bike passed the same visit. We count it separately from a clean first-time pass — it is 7.0% of tests overall.
Where does the data come from?
The DVSA anonymised MOT results dataset — every MOT test recorded in Great Britain — filtered to motorcycle test classes 1 and 2. This site analyses 18,679,309 tests across 2005–2025. It is public sector information used under the Open Government Licence v3.0.
How up to date is it?
The DVSA publishes the dataset in an annual drop. The site currently covers 2005–2025 and is refreshed when each new release lands.
What are test classes 1 and 2?
Class 1 covers motorcycles up to 200cc; class 2 covers all other motorcycles, including sidecar outfits. Mopeds and scooters sit in these classes too — anything tested as class 1 or 2 is included here.
Does a low pass rate mean a bike is bad?
Not by itself. Pass rates blend the machine with how it is used and maintained: commuter bikes rack up miles and winter salt, learner bikes get dropped, cherished classics get pampered. Treat the figures as reliability signals, not a lab test — and always weigh the test count behind a number.
Why do some bikes not appear?
Thresholds keep noise out: the make league needs 1,000+ tests, model rankings typically 150–200+, and registration-year cohorts 50+. A model with a handful of tests can swing wildly, so it is excluded rather than shown as a misleading number.
Why do very old bikes show high pass rates?
Survivor bias. A 40-year-old bike still being tested is, almost by definition, one that has been looked after — the neglected examples left the road long ago. That lifts the earliest registration-year cohorts.
Are advisories counted as failures?
No. Failure tables count defects that failed the test. Advisories — wear items flagged for attention — are excluded throughout.
Why median mileage instead of average?
A few bikes with six-figure odometers would drag an average upwards. The median — the middle bike — is a truer picture of typical use, so mileage figures here are medians.
Can I use these statistics?
Yes — the computed statistics are licensed CC BY 4.0. Cite bikereliability.co.uk and link the page the number came from. The underlying test records remain DVSA's, under OGL v3.0.
Something unanswered? Ask us — good questions end up on this page.