BIKERELIABILITY Reg check
League table/ Suzuki GSF600/vs Kawasaki ZX-6R
Head-to-head · 2005–2025

Data as of: DVSA MOT results to 2025

Suzuki GSF600 vs Kawasaki ZX-6R

The Kawasaki ZX-6R passes its MOT first time more often than the Suzuki GSF600: 78.1% vs 77.3%, a 0.8-point lead.

MOT reliability, side by side

first-time pass rate, outright fail rate and tests analysed · 2005–2025
Metric Suzuki GSF600 Kawasaki ZX-6R
First-time pass rate 77.3% 78.1%
Outright fail rate 14.2% 14.0%
Vs comparable bikes (age & mileage adjusted) -6.1 pts -5.8 pts
Engine size 599cc 599cc
Rank among all models #4013 of 5428 #3895 of 5428
Median miles at test 21,080 19,446
MOT tests analysed 143,023 173,956
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.

What fails, side by side

share of each bike's MOT tests that failed on the component · lower is better
Component Suzuki GSF600 Kawasaki ZX-6R
Lights & signalling 6.7% 6.1%
Brakes 6.1% 5.2%
Steering & suspension 3.6% 4.6%
Tyres & wheels 3.3% 3.6%
Structure & body 1.5% 1.2%
Drive system 1.4% 1.0%
Fuel & exhaust 1.2% 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 Suzuki GSF600 Kawasaki ZX-6R
2018 77.7% 78.5%
2019 76.7% 78.5%
2020 77.8% 78.1%
2021 76.8% 78.6%
2022 78.1% 79.4%
2023 78.2% 79.8%
2024 78.9% 80.3%
2025 79.6% 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 Suzuki GSF600 Kawasaki ZX-6R
0k-10k miles 86.8% 86.1%
10k-20k miles 80.1% 80.6%
20k-30k miles 75.2% 75.4%
30k-40k miles 71.3% 71.8%
40k-50k miles 69.4% 69.5%
50k-60k miles 68.3% 69.0%

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

Suzuki GSF600 vs Kawasaki ZX-6R FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Suzuki GSF600 or the Kawasaki ZX-6R?

The Kawasaki ZX-6R passes its MOT first time more often than the Suzuki GSF600: 78.1% vs 77.3%, a 0.8-point lead. Adjusted for age, mileage and test class the two are level (-6.1 vs -5.8 points against comparable bikes), so the raw gap is mostly down to how old and how used each fleet is. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Suzuki GSF600 fail its MOT on most?

Lights & signalling: 6.7% of Suzuki GSF600 MOT tests failed on it, then brakes (6.1%).

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 Suzuki GSF600 or the Kawasaki ZX-6R?

They are level: at 50k-60k miles the Suzuki GSF600 passes 68.3% first time and the Kawasaki ZX-6R 69.0%.

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