Bsa Royal Star vs Kawasaki ZX-6R

The Bsa Royal Star passes its MOT first time more often than the Kawasaki ZX-6R: 90.6% vs 78.1%, a 12.5-point lead.

MOT reliability, side by side

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

Metric	Bsa Royal Star	Kawasaki ZX-6R
First-time pass rate	90.6%	78.1%
Outright fail rate	3.0%	14.0%
Vs comparable bikes (age & mileage adjusted)	+5.7 pts	-5.8 pts
Engine size	500cc	599cc
Rank among all models	#776 of 5428	#3895 of 5428
Median miles at test	13,334	19,446
MOT tests analysed	361	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.

"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	Bsa Royal Star	Kawasaki ZX-6R
2006	96.8%	82.8%
2008	93.3%	78.4%
2012	90.3%	75.4%
2013	93.3%	75.5%
2015	88.6%	76.7%
2016	80.0%	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	Bsa Royal Star	Kawasaki ZX-6R
0k-10k miles	91.4%	86.1%
10k-20k miles	92.5%	80.6%
30k-40k miles	93.2%	71.8%

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

BSA ROYAL STAR 90.6% pass · 361 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.