Bsa C15 vs Yamaha YP250

The Bsa C15 passes its MOT first time more often than the Yamaha YP250: 89.2% vs 82.5%, a 6.7-point lead.

MOT reliability, side by side

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

Metric	Bsa C15	Yamaha YP250
First-time pass rate	89.2%	82.5%
Outright fail rate	5.3%	12.3%
Vs comparable bikes (age & mileage adjusted)	+2.1 pts	-2.3 pts
Engine size	250cc	249cc
Rank among all models	#1212 of 5428	#3073 of 5428
Median miles at test	14,157	15,613
MOT tests analysed	5,895	12,433
Most common failure	steering and suspension	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.

"Vs comparable bikes" is the first-time pass rate minus the rate expected for each bike's own mix of age, mileage and test class, in percentage points: positive means better than comparable bikes. How this works.

What fails, side by side

share of each bike's MOT tests that failed on the component · lower is better

Component	Bsa C15	Yamaha YP250
Steering & suspension	2.6%	5.0%
Brakes	1.3%	5.3%
Lights & signalling	2.4%	2.5%
Tyres & wheels	1.0%	3.8%
Fuel & exhaust	0.4%	0.8%
Structure & body	0.4%	0.5%
Drive system	0.3%	0.0%

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 C15	Yamaha YP250
2012	87.3%	83.9%
2013	89.4%	83.1%
2014	91.1%	81.4%
2015	91.8%	84.2%
2016	91.2%	79.8%
2017	94.8%	81.6%
2018	89.1%	82.9%
2019	94.1%	84.2%

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 C15	Yamaha YP250
0k-10k miles	89.7%	88.6%
10k-20k miles	88.5%	82.5%
20k-30k miles	89.2%	78.6%
30k-40k miles	88.4%	77.0%
40k-50k miles	86.2%	71.9%
50k-60k miles	92.1%	84.7%

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

Bsa C15 vs Yamaha YP250 FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Bsa C15 or the Yamaha YP250?

The Bsa C15 passes its MOT first time more often than the Yamaha YP250: 89.2% vs 82.5%, a 6.7-point lead. Adjusted for age, mileage and test class, the Bsa C15 still comes out ahead: +2.1 points vs comparable bikes for the Bsa C15, -2.3 for the Yamaha YP250. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Bsa C15 fail its MOT on most?

Steering & suspension: 2.6% of Bsa C15 MOT tests failed on it, then lights & signalling (2.4%).

What does the Yamaha YP250 fail its MOT on most?

Brakes: 5.3% of Yamaha YP250 MOT tests failed on it, then steering & suspension (5.0%).

Which holds up better at high mileage, the Bsa C15 or the Yamaha YP250?

At 50k-60k miles the Bsa C15 passes first time more often: 92.1% for the Bsa C15 vs 84.7% for the Yamaha YP250.

BSA C15 89.2% pass · 5,895 tests YAMAHA YP250 82.5% pass · 12.4k tests

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