Skyjet SJ 125-23 vs Gilera Runner

The Gilera Runner passes its MOT first time more often than the Skyjet SJ 125-23: 70.8% vs 44.7%, a 26.1-point lead.

MOT reliability, side by side

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

Metric	Skyjet SJ 125-23	Gilera Runner
First-time pass rate	44.7%	70.8%
Outright fail rate	44.7%	21.5%
Vs comparable bikes (age & mileage adjusted)	-29.6 pts	-0.7 pts
Engine size	125cc	124cc
Rank among all models	#5426 of 5428	#4675 of 5428
Median miles at test	6,185	11,381
MOT tests analysed	2,324	69,850
Most common failure	lighting and signalling	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	Skyjet SJ 125-23	Gilera Runner
Lights & signalling	31.2%	12.3%
Steering & suspension	23.8%	10.6%
Brakes	18.0%	7.2%
Tyres & wheels	10.8%	5.1%
Structure & body	11.7%	2.0%
Drive system	9.7%	0.0%
Fuel & exhaust	4.1%	2.6%

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	Skyjet SJ 125-23	Gilera Runner
2014	45.1%	70.6%
2015	47.2%	72.1%
2016	51.2%	73.3%
2017	47.2%	76.1%
2018	53.4%	77.2%
2019	59.0%	77.0%
2020	43.6%	75.8%
2021	48.5%	79.1%

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	Skyjet SJ 125-23	Gilera Runner
0k-10k miles	46.4%	76.2%
10k-20k miles	40.3%	67.5%
20k-30k miles	33.3%	65.4%

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

Skyjet SJ 125-23 vs Gilera Runner FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Skyjet SJ 125-23 or the Gilera Runner?

The Gilera Runner passes its MOT first time more often than the Skyjet SJ 125-23: 70.8% vs 44.7%, a 26.1-point lead. Adjusted for age, mileage and test class, the Gilera Runner still comes out ahead: -29.6 points vs comparable bikes for the Skyjet SJ 125-23, -0.7 for the Gilera Runner. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Skyjet SJ 125-23 fail its MOT on most?

Lights & signalling: 31.2% of Skyjet SJ 125-23 MOT tests failed on it, then steering & suspension (23.8%).

What does the Gilera Runner fail its MOT on most?

Lights & signalling: 12.3% of Gilera Runner MOT tests failed on it, then steering & suspension (10.6%).

Which holds up better at high mileage, the Skyjet SJ 125-23 or the Gilera Runner?

At 20k-30k miles the Gilera Runner passes first time more often: 33.3% for the Skyjet SJ 125-23 vs 65.4% for the Gilera Runner.

SKYJET SJ 125-23 44.7% pass · 2,324 tests GILERA RUNNER 70.8% pass · 69.9k tests

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