Bsa B31 vs Suzuki AN400

The Bsa B31 passes its MOT first time more often than the Suzuki AN400 — 92.0% vs 86.2%, a 5.8-point lead.

MOT reliability, side by side

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

Metric	Bsa B31	Suzuki AN400
First-time pass rate	92.0%	86.2%
Outright fail rate	3.1%	9.8%
Median miles at test	15,803	15,861
MOT tests analysed	3,429	27,056
Most common failure	lighting and signalling	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.

BSA B31 92.0% pass · 3,429 tests SUZUKI AN400 86.2% pass · 27.1k tests

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