Norton 99 vs Kawasaki ZX-6R

The Norton 99 passes its MOT first time more often than the Kawasaki ZX-6R: 93.6% vs 78.1%, a 15.5-point lead.

MOT reliability, side by side

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

Metric	Norton 99	Kawasaki ZX-6R
First-time pass rate	93.6%	78.1%
Outright fail rate	1.7%	14.0%
Engine size	600cc	599cc
Rank among all models	#224 of 5428	#3895 of 5428
Median miles at test	12,718	19,446
MOT tests analysed	767	173,956
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.

What fails, side by side

share of each bike's MOT tests that failed on the component · lower is better

Component	Norton 99	Kawasaki ZX-6R
Lights & signalling	0.4%	6.1%
Brakes	0.7%	5.2%
Steering & suspension	0.5%	4.6%
Tyres & wheels	0.5%	3.6%
Drive system	0.3%	1.0%
Structure & body	0%	1.2%
Fuel & exhaust	0%	0.8%

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	Norton 99	Kawasaki ZX-6R
2009	87.3%	76.6%
2010	92.6%	76.3%
2011	93.3%	76.6%
2012	89.7%	75.4%
2013	94.4%	75.5%
2014	91.9%	76.4%
2015	96.9%	76.7%
2016	93.8%	77.7%

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	Norton 99	Kawasaki ZX-6R
0k-10k miles	95.5%	86.1%
10k-20k miles	92.1%	80.6%
20k-30k miles	95.1%	75.4%
30k-40k miles	90.9%	71.8%
50k-60k miles	92.2%	69.0%

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

Norton 99 vs Kawasaki ZX-6R FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Norton 99 or the Kawasaki ZX-6R?

The Norton 99 passes its MOT first time more often than the Kawasaki ZX-6R: 93.6% vs 78.1%, a 15.5-point lead. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Norton 99 fail its MOT on most?

Brakes: 0.7% of Norton 99 MOT tests failed on it, then steering & suspension (0.5%).

What does the Kawasaki ZX-6R fail its MOT on most?

Lights & signalling: 6.1% of Kawasaki ZX-6R MOT tests failed on it, then brakes (5.2%).

Which holds up better at high mileage, the Norton 99 or the Kawasaki ZX-6R?

At 50k-60k miles the Norton 99 passes first time more often: 92.2% for the Norton 99 vs 69.0% for the Kawasaki ZX-6R.

NORTON 99 93.6% pass · 767 tests KAWASAKI ZX-6R 78.1% pass · 174k tests

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