Honda 400 Four: MOT pass rate by registration year

Which 400 Four years pass first time, and which fall short of the model's 86.2% average, from 1,030 DVSA tests.

1977

highest-passing year · 88.8%

1975

lowest-passing year · 83.3%

5.5pp

spread across 5 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: 1977 (88.8% of 321 tests). Lowest: 1975 (83.3% of 132). Years more than two points below the model average: 1975, 1979.

Registered	Tests	First-time pass	vs model (86.2%)
1975	132	83.3%	-2.9 pp
1976	207	85.5%	-0.7 pp
1977	321	88.8%	+2.6 pp
1978	242	88.4%	+2.2 pp
1979	60	83.3%	-2.9 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 · 2006–2017

Questions

Which 400 Four years have the lowest MOT pass rate?: 1975, 1979 registered examples pass first time less often than the Honda 400 Four overall (86.2%); the 1975 cohort is lowest at 83.3% from 132 tests.
Which 400 Four year has the highest MOT pass rate?: 1977, at 88.8% of 321 first tests (2005–2025). Years more than two points above the model average: 1977, 1978.
How much does the 400 Four pass rate vary by year?: 5.5 percentage points between the highest (1977, 88.8%) and lowest (1975, 83.3%) 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: Honda 400 Four reliability, failures and mileage · ranked #2148 of 5428 models· other Honda models: CBR600F, CBR900RR, CBR1100XX, CB500, C90, VFR800 Fi