Sunbeam S8 vs Suzuki GSF600

The Sunbeam S8 passes its MOT first time more often than the Suzuki GSF600: 91.4% vs 77.3%, a 14.1-point lead.

MOT reliability, side by side

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

Metric	Sunbeam S8	Suzuki GSF600
First-time pass rate	91.4%	77.3%
Outright fail rate	3.5%	14.2%
Engine size	500cc	599cc
Rank among all models	#588 of 5428	#4013 of 5428
Median miles at test	7,540	21,080
MOT tests analysed	1,319	143,023
Most common failure	brakes	brakes

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	Sunbeam S8	Suzuki GSF600
Brakes	1.9%	6.1%
Lights & signalling	1.3%	6.7%
Steering & suspension	1.1%	3.6%
Tyres & wheels	0.7%	3.3%
Structure & body	0.2%	1.5%
Drive system	0.2%	1.4%
Fuel & exhaust	0.2%	1.2%

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	Sunbeam S8	Suzuki GSF600
2005	92.3%	79.5%
2006	90.9%	81.8%
2007	94.2%	80.0%
2008	92.5%	78.4%
2009	88.1%	75.8%
2010	85.5%	75.8%
2011	95.2%	76.1%
2012	93.6%	75.9%

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	Sunbeam S8	Suzuki GSF600
0k-10k miles	92.3%	86.8%
10k-20k miles	90.2%	80.1%
20k-30k miles	89.5%	75.2%
30k-40k miles	88.9%	71.3%
40k-50k miles	90.9%	69.4%
50k-60k miles	94.9%	68.3%

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

Sunbeam S8 vs Suzuki GSF600 FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Sunbeam S8 or the Suzuki GSF600?

The Sunbeam S8 passes its MOT first time more often than the Suzuki GSF600: 91.4% vs 77.3%, a 14.1-point lead. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Sunbeam S8 fail its MOT on most?

Brakes: 1.9% of Sunbeam S8 MOT tests failed on it, then lights & signalling (1.3%).

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%).

Which holds up better at high mileage, the Sunbeam S8 or the Suzuki GSF600?

At 50k-60k miles the Sunbeam S8 passes first time more often: 94.9% for the Sunbeam S8 vs 68.3% for the Suzuki GSF600.

SUNBEAM S8 91.4% pass · 1,319 tests SUZUKI GSF600 77.3% pass · 143k tests

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