Ajs Nac 12 vs Gilera Runner

The Gilera Runner passes its MOT first time more often than the Ajs Nac 12: 70.8% vs 61.3%, a 9.5-point lead.

MOT reliability, side by side

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

Metric	Ajs Nac 12	Gilera Runner
First-time pass rate	61.3%	70.8%
Outright fail rate	21.8%	21.5%
Vs comparable bikes (age & mileage adjusted)	-13.1 pts	-0.7 pts
Engine size	124cc	124cc
Rank among all models	#5171 of 5428	#4675 of 5428
Median miles at test	5,772	11,381
MOT tests analysed	463	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.

Pass rate by test year

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

Test year	Ajs Nac 12	Gilera Runner
2013	68.2%	69.5%
2014	60.6%	70.6%
2015	58.4%	72.1%
2016	66.7%	73.3%
2017	61.8%	76.1%

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	Ajs Nac 12	Gilera Runner
0k-10k miles	63.0%	76.2%
10k-20k miles	52.8%	67.5%

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

AJS NAC 12 61.3% pass · 463 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.