Bsa C12 vs Yamaha WR250F

The Bsa C12 passes its MOT first time more often than the Yamaha WR250F: 91.7% vs 78.0%, a 13.7-point lead.

MOT reliability, side by side

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

Metric	Bsa C12	Yamaha WR250F
First-time pass rate	91.7%	78.0%
Outright fail rate	4.7%	12.8%
Engine size	250cc	249cc
Rank among all models	#524 of 5428	#3913 of 5428
Median miles at test	12,950	3,018
MOT tests analysed	553	10,465
Most common failure	steering and suspension	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 C12	Yamaha WR250F
Lights & signalling	1.4%	8.2%
Steering & suspension	2.5%	5.1%
Tyres & wheels	1.4%	3.0%
Brakes	1.1%	2.2%
Structure & body	0.5%	0.5%
Drive system	0%	0.7%
Fuel & exhaust	0%	0.4%

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 C12	Yamaha WR250F
2006	93.4%	76.7%
2007	88.4%	73.3%
2008	91.0%	78.2%
2009	91.0%	73.9%
2010	94.3%	75.3%
2011	88.9%	76.7%
2012	91.4%	76.5%

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 C12	Yamaha WR250F
0k-10k miles	91.4%	78.1%
10k-20k miles	96.0%	77.3%
20k-30k miles	88.0%	67.9%

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

Bsa C12 vs Yamaha WR250F FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Bsa C12 or the Yamaha WR250F?

The Bsa C12 passes its MOT first time more often than the Yamaha WR250F: 91.7% vs 78.0%, a 13.7-point lead. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Bsa C12 fail its MOT on most?

Steering & suspension: 2.5% of Bsa C12 MOT tests failed on it, then lights & signalling (1.4%).

What does the Yamaha WR250F fail its MOT on most?

Lights & signalling: 8.2% of Yamaha WR250F MOT tests failed on it, then steering & suspension (5.1%).

Which holds up better at high mileage, the Bsa C12 or the Yamaha WR250F?

At 20k-30k miles the Bsa C12 passes first time more often: 88.0% for the Bsa C12 vs 67.9% for the Yamaha WR250F.

BSA C12 91.7% pass · 553 tests YAMAHA WR250F 78.0% pass · 10.5k tests

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