Zongshen ZS 125-50 Ranger vs Yamaha YBR 125

The Yamaha YBR 125 passes its MOT first time more often than the Zongshen ZS 125-50 Ranger: 71.0% vs 70.7%, a 0.3-point lead.

MOT reliability, side by side

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

Metric	Zongshen ZS 125-50 Ranger	Yamaha YBR 125
First-time pass rate	70.7%	71.0%
Outright fail rate	20.7%	17.1%
Vs comparable bikes (age & mileage adjusted)	-2.8 pts	-1.1 pts
Engine size	124cc	124cc
Rank among all models	#4685 of 5428	#4664 of 5428
Median miles at test	8,281	10,652
MOT tests analysed	420	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.

Pass rate by test year

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

Test year	Zongshen ZS 125-50 Ranger	Yamaha YBR 125
2014	68.4%	70.0%
2015	71.0%	71.2%
2016	66.7%	71.3%
2017	63.9%	70.7%
2018	73.0%	72.0%
2019	80.6%	71.8%

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	Zongshen ZS 125-50 Ranger	Yamaha YBR 125
0k-10k miles	77.5%	76.8%
10k-20k miles	64.0%	67.4%
20k-30k miles	64.4%	63.8%

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

ZONGSHEN ZS 125-50 RANGER 70.7% pass · 420 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.