BIKERELIABILITY Reg check
League table/ Ajs 350/vs Kawasaki ZXR400
Head-to-head · 2005–2025

Data as of: DVSA MOT results to 2025

Ajs 350 vs Kawasaki ZXR400

The Ajs 350 passes its MOT first time more often than the Kawasaki ZXR400: 88.7% vs 73.1%, a 15.6-point lead.

MOT reliability, side by side

first-time pass rate, outright fail rate and tests analysed · 2005–2025
Metric Ajs 350 Kawasaki ZXR400
First-time pass rate 88.7% 73.1%
Outright fail rate 4.1% 18.9%
Engine size 350cc 398cc
Rank among all models #1370 of 5428 #4490 of 5428
Median miles at test 12,350 23,651
MOT tests analysed 486 14,200
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.

Pass rate by test year

first-time MOT pass rate in each calendar year both bikes were tested
Test year Ajs 350 Kawasaki ZXR400
2006 90.8% 73.0%
2007 85.5% 72.3%
2008 88.5% 72.6%
2009 90.0% 70.1%
2010 88.2% 68.5%
2011 85.1% 71.2%
2012 86.0% 69.5%

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 350 Kawasaki ZXR400
0k-10k miles 90.7% 87.1%
10k-20k miles 93.3% 77.4%
20k-30k miles 86.9% 69.9%
30k-40k miles 81.8% 67.8%

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

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