MZ ETZ125 vs Yamaha YBR 125

The MZ ETZ125 passes its MOT first time more often than the Yamaha YBR 125: 77.6% vs 71.0%, a 6.6-point lead.

MOT reliability, side by side

first-time pass rate, outright fail rate and tests analysed · 2005–2025

Metric	MZ ETZ125	Yamaha YBR 125
First-time pass rate	77.6%	71.0%
Outright fail rate	13.5%	17.1%
Vs comparable bikes (age & mileage adjusted)	+2.5 pts	-1.1 pts
Engine size	123cc	124cc
Rank among all models	#3965 of 5428	#4664 of 5428
Median miles at test	17,901	10,652
MOT tests analysed	1,000	124,897
Most common failure	lighting and signalling	brakes

First-time outcomes on normal tests, 2005–2025. "Most common failure" is the component group with the most recorded defects on failed tests. Read pass rates against test counts: a smaller sample is noisier. Source: DVSA anonymised MOT results.

"Vs comparable bikes" is the first-time pass rate minus the rate expected for each bike's own mix of age, mileage and test class, in percentage points: positive means better than comparable bikes. How this works.

What fails, side by side

share of each bike's MOT tests that failed on the component · lower is better

Component	MZ ETZ125	Yamaha YBR 125
Lights & signalling	7.4%	8.5%
Brakes	5.4%	5.9%
Steering & suspension	4.5%	6.5%
Tyres & wheels	3.5%	4.4%
Structure & body	1.6%	3.8%
Drive system	0.1%	2.9%
Fuel & exhaust	1.1%	0.6%

A test that fails on two components counts once in each. Component links go to the bikes most likely to fail on it.

Pass rate by test year

first-time MOT pass rate in each calendar year both bikes were tested

Test year	MZ ETZ125	Yamaha YBR 125
2011	74.2%	69.1%
2012	71.4%	69.1%
2013	71.9%	69.5%
2014	82.4%	70.0%
2015	79.6%	71.2%
2016	78.9%	71.3%
2017	79.5%	70.7%
2018	93.8%	72.0%

Each year mixes bikes of different ages, so a fleet that is getting older tends to slip.

Pass rate by mileage

first-time MOT pass rate by miles on the clock at test

Mileage	MZ ETZ125	Yamaha YBR 125
0k-10k miles	79.4%	76.8%
10k-20k miles	79.3%	67.4%
20k-30k miles	76.0%	63.8%
30k-40k miles	75.8%	62.2%
40k-50k miles	72.3%	63.4%
50k-60k miles	70.2%	63.6%

Bands with fewer than 30 tests for either bike are left out.

MZ ETZ125 vs Yamaha YBR 125 FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the MZ ETZ125 or the Yamaha YBR 125?

The MZ ETZ125 passes its MOT first time more often than the Yamaha YBR 125: 77.6% vs 71.0%, a 6.6-point lead. Adjusted for age, mileage and test class, the MZ ETZ125 still comes out ahead: +2.5 points vs comparable bikes for the MZ ETZ125, -1.1 for the Yamaha YBR 125. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the MZ ETZ125 fail its MOT on most?

Lights & signalling: 7.4% of MZ ETZ125 MOT tests failed on it, then brakes (5.4%).

What does the Yamaha YBR 125 fail its MOT on most?

Lights & signalling: 8.5% of Yamaha YBR 125 MOT tests failed on it, then steering & suspension (6.5%).

Which holds up better at high mileage, the MZ ETZ125 or the Yamaha YBR 125?

At 50k-60k miles the MZ ETZ125 passes first time more often: 70.2% for the MZ ETZ125 vs 63.6% for the Yamaha YBR 125.

MZ ETZ125 77.6% pass · 1,000 tests YAMAHA YBR 125 71.0% pass · 125k tests

See each bike's full report (trend, mileage curve, failure breakdown and rivals) on its own page.