Triumph 21 vs Suzuki AN400

The Triumph 21 passes its MOT first time more often than the Suzuki AN400: 93.8% vs 86.2%, a 7.6-point lead.

MOT reliability, side by side

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

Metric	Triumph 21	Suzuki AN400
First-time pass rate	93.8%	86.2%
Outright fail rate	2.2%	9.8%
Engine size	350cc	385cc
Rank among all models	#198 of 5428	#2148 of 5428
Median miles at test	19,231	15,861
MOT tests analysed	451	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.

Pass rate by test year

first-time MOT pass rate in each calendar year both bikes were tested

Test year	Triumph 21	Suzuki AN400
2007	91.4%	88.6%
2008	92.9%	87.6%
2009	94.9%	87.0%
2010	97.9%	86.9%
2011	93.8%	84.6%
2012	95.6%	85.5%
2013	93.3%	86.9%
2014	83.3%	85.0%

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	Triumph 21	Suzuki AN400
0k-10k miles	90.6%	91.7%
10k-20k miles	93.7%	86.7%
20k-30k miles	94.6%	82.7%
30k-40k miles	92.2%	81.0%
40k-50k miles	96.9%	79.7%
50k-60k miles	97.2%	75.7%

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

TRIUMPH 21 93.8% pass · 451 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.