Royal Enfield Bullet Efi E4 vs Kawasaki ZX-6R

The Royal Enfield Bullet Efi E4 passes its MOT first time more often than the Kawasaki ZX-6R: 89.6% vs 78.1%, a 11.5-point lead.

MOT reliability, side by side

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

Metric	Royal Enfield Bullet Efi E4	Kawasaki ZX-6R
First-time pass rate	89.6%	78.1%
Outright fail rate	4.8%	14.0%
Vs comparable bikes (age & mileage adjusted)	-0.1 pts	-5.8 pts
Engine size	499cc	599cc
Rank among all models	#1077 of 5428	#3895 of 5428
Median miles at test	4,013	19,446
MOT tests analysed	897	173,956
Most common failure	lamps and reflectors	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.

What fails, side by side

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

Component	Royal Enfield Bullet Efi E4	Kawasaki ZX-6R
Lights & signalling	2.1%	6.1%
Brakes	1.4%	5.2%
Steering & suspension	0.4%	4.6%
Tyres & wheels	1.0%	3.6%
Structure & body	0.9%	1.2%
Drive system	0%	1.0%
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	Royal Enfield Bullet Efi E4	Kawasaki ZX-6R
2020	96.3%	78.1%
2021	84.6%	78.6%
2022	89.5%	79.4%
2023	90.2%	79.8%
2024	85.7%	80.3%
2025	93.3%	81.1%

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	Royal Enfield Bullet Efi E4	Kawasaki ZX-6R
0k-10k miles	90.2%	86.1%
10k-20k miles	82.9%	80.6%

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

Royal Enfield Bullet Efi E4 vs Kawasaki ZX-6R FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Royal Enfield Bullet Efi E4 or the Kawasaki ZX-6R?

The Royal Enfield Bullet Efi E4 passes its MOT first time more often than the Kawasaki ZX-6R: 89.6% vs 78.1%, a 11.5-point lead. Adjusted for age, mileage and test class, the Royal Enfield Bullet Efi E4 still comes out ahead: -0.1 points vs comparable bikes for the Royal Enfield Bullet Efi E4, -5.8 for the Kawasaki ZX-6R. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Royal Enfield Bullet Efi E4 fail its MOT on most?

Lights & signalling: 2.1% of Royal Enfield Bullet Efi E4 MOT tests failed on it, then brakes (1.4%).

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%).

ROYAL ENFIELD BULLET EFI E4 89.6% pass · 897 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.