BIKERELIABILITY Reg check
League table/ Derbi GPR 125 09/vs Yamaha YBR 125
Head-to-head · 2005–2025

Data as of: DVSA MOT results to 2025

Derbi GPR 125 09 vs Yamaha YBR 125

The Yamaha YBR 125 passes its MOT first time more often than the Derbi GPR 125 09: 71.0% vs 64.6%, a 6.4-point lead.

MOT reliability, side by side

first-time pass rate, outright fail rate and tests analysed · 2005–2025
Metric Derbi GPR 125 09 Yamaha YBR 125
First-time pass rate 64.6% 71.0%
Outright fail rate 25.6% 17.1%
Vs comparable bikes (age & mileage adjusted) -10.2 pts -1.1 pts
Engine size 124cc 124cc
Rank among all models #5035 of 5428 #4664 of 5428
Median miles at test 5,991 10,652
MOT tests analysed 582 124,897
Most common failure brakes 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 Derbi GPR 125 09 Yamaha YBR 125
Lights & signalling 11.9% 8.5%
Brakes 13.1% 5.9%
Steering & suspension 9.8% 6.5%
Structure & body 5.7% 3.8%
Tyres & wheels 3.8% 4.4%
Drive system 4.6% 2.9%
Fuel & exhaust 1.5% 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 Derbi GPR 125 09 Yamaha YBR 125
2013 63.6% 69.5%
2014 62.0% 70.0%
2015 61.9% 71.2%
2016 70.7% 71.3%
2017 62.9% 70.7%
2018 56.3% 72.0%
2020 51.5% 73.4%

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 Derbi GPR 125 09 Yamaha YBR 125
0k-10k miles 65.4% 76.8%
10k-20k miles 59.7% 67.4%

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

Derbi GPR 125 09 vs Yamaha YBR 125 FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Derbi GPR 125 09 or the Yamaha YBR 125?

The Yamaha YBR 125 passes its MOT first time more often than the Derbi GPR 125 09: 71.0% vs 64.6%, a 6.4-point lead. Adjusted for age, mileage and test class, the Yamaha YBR 125 still comes out ahead: -10.2 points vs comparable bikes for the Derbi GPR 125 09, -1.1 for the Yamaha YBR 125. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Derbi GPR 125 09 fail its MOT on most?

Brakes: 13.1% of Derbi GPR 125 09 MOT tests failed on it, then lights & signalling (11.9%).

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%).

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