Yamaha XJ550: MOT pass rate by registration year

Which XJ550 years pass first time, and which fall short of the model's 76.1% average, from 1,569 DVSA tests.

1984

highest-passing year · 77.4%

1982

lowest-passing year · 74.5%

2.9pp

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: 1984 (77.4% of 84 tests). Lowest: 1982 (74.5% of 420).

Registered	Tests	First-time pass	vs model (76.1%)
1981	715	77.1%	+1.0 pp
1982	420	74.5%	-1.6 pp
1983	170	75.3%	-0.8 pp
1984	84	77.4%	+1.3 pp
1985	63	74.6%	-1.5 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 · 2005–2022

Questions

Which XJ550 years have the lowest MOT pass rate?: none: no registration year of the Yamaha XJ550 falls more than two points under the model's 76.1% overall pass rate.
Which XJ550 year has the highest MOT pass rate?: 1984, at 77.4% of 84 first tests (2005–2025).
How much does the XJ550 pass rate vary by year?: 2.9 percentage points between the highest (1984, 77.4%) and lowest (1982, 74.5%) 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: Yamaha XJ550 reliability, failures and mileage · ranked #4173 of 5428 models· other Yamaha models: YZF-R1, YZF-R6, FZS600, YBR 125, XJR1300, FZ6