BIKERELIABILITY Reg check
League table/ Jianshe JS/vs Yamaha YBR 125
Head-to-head · 2005–2025

Data as of: DVSA MOT results to 2025

Jianshe JS vs Yamaha YBR 125

The Yamaha YBR 125 passes its MOT first time more often than the Jianshe JS: 71.0% vs 64.5%, a 6.5-point lead.

MOT reliability, side by side

first-time pass rate, outright fail rate and tests analysed · 2005–2025
Metric Jianshe JS Yamaha YBR 125
First-time pass rate 64.5% 71.0%
Outright fail rate 24.6% 17.1%
Vs comparable bikes (age & mileage adjusted) -8.3 pts -1.1 pts
Engine size 124cc 124cc
Rank among all models #5038 of 5428 #4664 of 5428
Median miles at test 8,902 10,652
MOT tests analysed 211 124,897
Most common failure lamps and reflectors 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 Jianshe JS Yamaha YBR 125
2017 65.3% 70.7%
2018 72.7% 72.0%
2019 67.7% 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 Jianshe JS Yamaha YBR 125
0k-10k miles 66.1% 76.8%
10k-20k miles 65.5% 67.4%

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

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