BIKERELIABILITY Reg check
Model report · 2005–2025

AJS ECO

123cc Petrol Class 1
66.9%
first-time pass rate
22.1%
failed outright
8,395
median miles at test
145
MOT tests, 2005–2025
-4.7pp
vs expected · age & mileage

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.

“vs expected” adjusts for age, mileage and test class, so a cherished classic and a hard-used commuter are compared fairly. How this works.

What fails on a ECO

failure defects by component group · advisories excluded
Component group Share of defects Defects % of defects
lamps and reflectors
29 29.9
brakes
17 17.5
suspension
13 13.4
structure and attachments
13 13.4
tyres
8 8.2
steering
6 6.2
lighting and signalling
5 5.2
drive system
3 3.1
steering and suspension
2 2.1
audible warning (Horn)
1 1

Defects recorded against failed normal tests, 2005–2025, grouped by DVSA inspection section. One test can record multiple defects.

How rivals compare

same type, similar capacity, high test volume

On first-time pass rate the ECO beats 0 of its 4 closest rivals (YAMAHA YBR 125, HONDA CG125, HONDA CBF125).

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 ECO.

Compare with any bike

rival not listed above? pick any model to see it head-to-head with the Eco

Pass rate by registration year

how each model-year cohort fares · registration year from first use date

Best year to buy used: 2016 (60.0% pass). Weakest: 2016 (60.0%).

First-time pass rate by the year each bike was first registered (cohorts with ≥ 50 tests). Older cohorts are survivors: the worst examples have already left the road, which tends to lift the earliest years.

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