Mutt Mongrel 125 vs Honda CG125

The Honda CG125 passes its MOT first time more often than the Mutt Mongrel 125: 72.2% vs 69.0%, a 3.2-point lead.

MOT reliability, side by side

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

Metric	Mutt Mongrel 125	Honda CG125
First-time pass rate	69.0%	72.2%
Outright fail rate	19.9%	16.8%
Vs comparable bikes (age & mileage adjusted)	-9.2 pts	+0.7 pts
Engine size	125cc	124cc
Rank among all models	#4799 of 5428	#4568 of 5428
Median miles at test	3,762	17,460
MOT tests analysed	3,527	89,345
Most common failure	lamps and reflectors	lighting and signalling

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	Mutt Mongrel 125	Honda CG125
Lights & signalling	12.5%	10.0%
Brakes	8.7%	5.1%
Steering & suspension	5.0%	7.2%
Structure & body	5.2%	1.9%
Tyres & wheels	2.4%	4.6%
Drive system	0%	2.6%
Fuel & exhaust	0%	0.9%

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	Mutt Mongrel 125	Honda CG125
2019	57.1%	71.8%
2020	77.5%	73.6%
2021	65.7%	73.9%
2022	68.3%	73.5%
2023	69.0%	74.4%
2024	68.4%	73.0%
2025	68.8%	76.4%

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	Mutt Mongrel 125	Honda CG125
0k-10k miles	68.3%	79.3%
10k-20k miles	62.3%	73.0%
20k-30k miles	62.7%	68.3%

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

Mutt Mongrel 125 vs Honda CG125 FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Mutt Mongrel 125 or the Honda CG125?

The Honda CG125 passes its MOT first time more often than the Mutt Mongrel 125: 72.2% vs 69.0%, a 3.2-point lead. Adjusted for age, mileage and test class, the Honda CG125 still comes out ahead: -9.2 points vs comparable bikes for the Mutt Mongrel 125, +0.7 for the Honda CG125. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Mutt Mongrel 125 fail its MOT on most?

Lights & signalling: 12.5% of Mutt Mongrel 125 MOT tests failed on it, then brakes (8.7%).

What does the Honda CG125 fail its MOT on most?

Lights & signalling: 10.0% of Honda CG125 MOT tests failed on it, then steering & suspension (7.2%).

Which holds up better at high mileage, the Mutt Mongrel 125 or the Honda CG125?

At 20k-30k miles the Honda CG125 passes first time more often: 62.7% for the Mutt Mongrel 125 vs 68.3% for the Honda CG125.

MUTT MONGREL 125 69.0% pass · 3,527 tests HONDA CG125 72.2% pass · 89.3k tests

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