Bsa C12: MOT pass rate by registration year

Which C12 years pass first time, and which fall short of the model's 91.7% average, from 553 DVSA tests.

1956

highest-passing year · 94.7%

1958

lowest-passing year · 90.4%

4.3pp

spread across 3 years

Pass rate by registration year

first-time pass rate · cohorts with 50 or more tests · registration year from first use date

Highest pass rate: 1956 (94.7% of 132 tests). Lowest: 1958 (90.4% of 178).

Registered	Tests	First-time pass	vs model (91.7%)
1956	132	94.7%	+3.0 pp
1957	158	90.5%	-1.2 pp
1958	178	90.4%	-1.3 pp

Older cohorts are survivors: the worst examples have already left the road, which tends to lift the earliest years. A first-time MOT pass is a roadworthiness check, not a full mechanical inspection.

Pass rate over time

first-time pass rate by test year · 2006–2012

Questions

Which C12 years have the lowest MOT pass rate?: none: no registration year of the Bsa C12 falls more than two points under the model's 91.7% overall pass rate.
Which C12 year has the highest MOT pass rate?: 1956, at 94.7% of 132 first tests (2005–2025).
How much does the C12 pass rate vary by year?: 4.3 percentage points between the highest (1956, 94.7%) and lowest (1958, 90.4%) cohorts with at least 50 tests. Older cohorts are survivors: the worst examples have already left the road, which tends to lift the earliest years.

Full report: Bsa C12 reliability, failures and mileage · ranked #524 of 5428 models· other Bsa models: A10, Bantam, C15, A65, B31, B40