Bsa M20 vs Suzuki SV650S

The Bsa M20 passes its MOT first time more often than the Suzuki SV650S: 91.4% vs 80.6%, a 10.8-point lead.

MOT reliability, side by side

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

Metric	Bsa M20	Suzuki SV650S
First-time pass rate	91.4%	80.6%
Outright fail rate	2.5%	11.9%
Engine size	500cc	645cc
Rank among all models	#588 of 5428	#3459 of 5428
Median miles at test	7,746	16,958
MOT tests analysed	1,295	84,632
Most common failure	lighting and signalling	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	Bsa M20	Suzuki SV650S
Lights & signalling	1.1%	5.0%
Brakes	1.1%	4.7%
Steering & suspension	0.9%	2.5%
Tyres & wheels	0.4%	3.0%
Drive system	0%	1.2%
Fuel & exhaust	0.4%	0.8%
Structure & body	0.1%	0.9%

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	Bsa M20	Suzuki SV650S
2008	90.2%	82.8%
2009	87.3%	80.5%
2010	92.1%	80.3%
2011	91.8%	80.0%
2012	84.8%	78.8%
2013	91.9%	77.9%
2014	88.6%	78.3%
2015	94.4%	78.6%

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 M20	Suzuki SV650S
0k-10k miles	90.9%	88.2%
10k-20k miles	94.1%	81.6%
20k-30k miles	92.8%	76.9%
30k-40k miles	80.9%	73.6%
40k-50k miles	92.8%	73.3%

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

Bsa M20 vs Suzuki SV650S FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Bsa M20 or the Suzuki SV650S?

The Bsa M20 passes its MOT first time more often than the Suzuki SV650S: 91.4% vs 80.6%, a 10.8-point lead. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Bsa M20 fail its MOT on most?

Lights & signalling: 1.1% of Bsa M20 MOT tests failed on it, then brakes (1.1%).

What does the Suzuki SV650S fail its MOT on most?

Lights & signalling: 5.0% of Suzuki SV650S MOT tests failed on it, then brakes (4.7%).

Which holds up better at high mileage, the Bsa M20 or the Suzuki SV650S?

At 40k-50k miles the Bsa M20 passes first time more often: 92.8% for the Bsa M20 vs 73.3% for the Suzuki SV650S.

BSA M20 91.4% pass · 1,295 tests SUZUKI SV650S 80.6% pass · 84.6k tests

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