BIKERELIABILITY Reg check
League table/ MZ/125SX
Model report · 2005–2025

MZ 125SX

124cc Petrol Class 1
#4940 of 5428 overall #19 of 20 MZs #485 of 734 commuter bikes
66.5%
first-time pass rate
22.8%
failed outright
14,974
median miles at test
263
MOT tests, 2005–2025
-4.6pp
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.

Pass rate by mileage

how the 125SX's first-time pass rate falls with the odometer · class average 73.4%

A low-mileage 125SX passes first time 76.1% of the time; by 20k that's 62.8%.

56%68%79%0k: 76.1% pass (92 tests)10k: 59.3% pass (81 tests)20k: 62.8% pass (43 tests)0k10k20k

First-time pass rate by odometer reading at test, 10,000-mile bands for this model. Mileage is the strongest reliability signal. See the full curve.

What fails on a 125SX

failure defects by component group · advisories excluded
Component group Share of defects Defects % of defects
lighting and signalling
66 34.7
brakes
41 21.6
steering and suspension
27 14.2
drive system
23 12.1
tyres and wheels
13 6.8
lamps and reflectors
11 5.8
body and structure
4 2.1
driving controls
2 1.1
wheels
2 1.1
structure and attachments
1 0.5

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 125SX beats 0 of its 4 closest rivals (YAMAHA YBR 125, HONDA CG125, HONDA CBF125).

YAMAHA YBR 125 71.0% pass · 125k tests Compare head-to-head →
HONDA CG125 72.2% pass · 89.3k tests Compare head-to-head →
HONDA CBF125 73.3% pass · 84.4k tests Compare head-to-head →
GILERA RUNNER 70.8% pass · 69.9k tests Compare head-to-head →

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 125SX.

Compare with any bike

rival not listed above? pick any model to see it head-to-head with the 125SX

More MZ models

other MZ bikes ranked by MOT pass rate
MZ BAGHIRA 80.6% pass · 2,702 tests
MZ ETZ250 86.6% pass · 2,568 tests
MZ SKORPION 82.0% pass · 1,626 tests
MZ ETZ251 85.7% pass · 1,621 tests
MZ TS250 88.4% pass · 1,408 tests
MZ ETZ125 77.6% pass · 1,000 tests

See all MZ models →

Pass rate by registration year

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

Best year to buy used: 2002 (76.3% pass). Weakest: 2004 (66.7%).

65%72%78%2002: 76.3% pass (76 tests)2004: 66.7% pass (69 tests)20022004

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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