Ariel NH350 vs Kawasaki ZXR400

The Ariel NH350 passes its MOT first time more often than the Kawasaki ZXR400: 93.6% vs 73.1%, a 20.5-point lead.

MOT reliability, side by side

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

Metric	Ariel NH350	Kawasaki ZXR400
First-time pass rate	93.6%	73.1%
Outright fail rate	3.5%	18.9%
Engine size	350cc	398cc
Rank among all models	#224 of 5428	#4490 of 5428
Median miles at test	26,315	23,651
MOT tests analysed	282	14,200
Most common failure	brakes	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.

Pass rate by test year

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

Test year	Ariel NH350	Kawasaki ZXR400
2006	97.7%	73.0%
2007	100.0%	72.3%
2008	87.9%	72.6%
2009	91.9%	70.1%
2011	94.9%	71.2%

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	Ariel NH350	Kawasaki ZXR400
0k-10k miles	93.5%	87.1%
20k-30k miles	92.9%	69.9%
30k-40k miles	92.5%	67.8%
40k-50k miles	90.6%	64.7%

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

ARIEL NH350 93.6% pass · 282 tests KAWASAKI ZXR400 73.1% pass · 14.2k tests

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